Dr Zhaohui Wang

Dr Zhaohui Wang

Conjoint Senior Lecturer

School of Environmental and Life Sciences

Career Summary

Biography

Dr Zhaohui Wang received his PhD degree in Physical Chemistry (2009) from Institute of Chemistry, Chinese Academy of Sciences, China. He is currently a Conjoint Senior Research Fellow at International Centre for Balanced Land Use at the University of Newcastle, Australia. Prior to this Dr Wang worked as an Associate Professor at College of Environmental Science and Engineering, Donghua University, China and as a Research Associate at Southern Cross GeoScience, Southern Cross University, Australia, respectively. His career has been dedicated to fundamental discovery on environmental chemistry of redox-active elements, focusing specifically on Fe, Cl and Cr cycles both in natural and engineered systems. Dr Wang is the (co)author of over 70 peer-reviewed journal articles and 4 book chapters. To date his publications have received over 2700 citations (Google Scholar), with an H-index of 23 (i10-index of 45). He has served as an Associate Editor for RSC Advances (Royal Society of Chemistry) since 2015.


Qualifications

  • PhD, Graduat University of Chinese Academy of Sciences

Keywords

  • Advanced oxidation processes
  • Chemical intermediates
  • Environmental catalysis
  • Environmental geochemistry
  • Environmental photochemistry
  • Environmental redox chemistry
  • Radical chemistry

Languages

  • Mandarin (Mother)
  • English (Fluent)

Fields of Research

Code Description Percentage
039901 Environmental Chemistry (incl. Atmospheric Chemistry) 50
040202 Inorganic Geochemistry 25
090409 Wastewater Treatment Processes 25

Professional Experience

UON Appointment

Title Organisation / Department
Senior Lecturer University of Newcastle
School of Environmental and Life Sciences
Australia

Grant Reviews

Year Grant Amount
2017 ARC FT DP DE
Aust Competitive - Commonwealth - 1CS, Aust Competitive - Commonwealth - 1CS
$1,000,000

Prestigious works

Year Commenced Year Finished Prestigious Work Role
2015 2018 Associate Editor RSC Editor
Edit

Publications

For publications that are currently unpublished or in-press, details are shown in italics.


Chapter (3 outputs)

Year Citation Altmetrics Link
2013 Wang Z, Chen C, Ma W, Zhao J, 'Sensitization of Titania Semiconductor: A Promising Strategy to Utilize Visible Light', Photocatalysis and Water Purification: From Fundamentals to Recent Applications 199-240 (2013)
DOI 10.1002/9783527645404.ch8
Citations Scopus - 7
2012 Zhang DQ, Zhan XW, Wang ZH, Pei J, Zhang GX, Zhu DB, et al., 'Organic p-Conjugated Molecules for Organic Semiconductors and Photovoltaic Materials', Organic Chemistry: Breakthroughs and Perspectives 759-780 (2012)
DOI 10.1002/9783527664801.ch20
Citations Scopus - 1
2011 Chen C, Wang Z, Ma W, Ji H, Zhao J, 'Photocatalytic Degradation of Organic Contaminants on Mineral Surfaces', Biophysico-Chemical Processes of Anthropogenic Organic Compounds in Environmental Systems 91-111 (2011)
DOI 10.1002/9780470944479.ch4
Citations Scopus - 2

Journal article (250 outputs)

Year Citation Altmetrics Link
2018 Zeng C, Meng D, Jiang W, Wang Z, 'Synthesis of Isomeric Perylenodithiophene Diimides', Organic Letters, 20 6606-6609 (2018)

© 2018 American Chemical Society. Two isoelectronic dithiophene-fused perylene diimides (PDTI-1 and PDTI-2) were synthesized via a "bay-derivatization toward lateral extensio... [more]

© 2018 American Chemical Society. Two isoelectronic dithiophene-fused perylene diimides (PDTI-1 and PDTI-2) were synthesized via a "bay-derivatization toward lateral extension" strategy. Single-crystal analysis unambiguously confirmed their unique structures and packing arrangements. The new PDTI system manifested significantly red-shifted absorptions with intense bands at 500-700 nm. Further dimerization indicated the potential of these dithiophene-fused PDIs as new building blocks for the construction of versatile rylene dyes in optoelectronic devices.

DOI 10.1021/acs.orglett.8b02983
2018 Zeng C, Xiao C, Feng X, Zhang L, Jiang W, Wang Z, 'Electron-Transporting Bis(heterotetracenes) with Tunable Helical Packing', Angewandte Chemie - International Edition, 57 10933-10937 (2018)

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A novel kind of electron-deficient bis(heterotetracenes) namely perylenotetrathiophenediimides (PTTIs) involving double S-h... [more]

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A novel kind of electron-deficient bis(heterotetracenes) namely perylenotetrathiophenediimides (PTTIs) involving double S-hetero[5]helicene diimides, is developed by a fourfold thienannulation route via ortho-functionalization of perylene diimides (PDIs). PTTIs exhibit significantly red-shifted absorption capacity with lowest-energy transition maxima beyond 700 nm and narrowed HOMO¿LUMO energy gaps. Through delicately tuning the side-chain substitution, the distorted propeller-like framework could self-assemble into unprecedented 1D helical p-stacking structures with short p¿p contacts and rich nonbonding interactions from alternating arrangements of P/M enantiomeric couples or tetrads. Excellent electron transporting efficiency in racemate PTTI crystals with 0.40 cm2 V-1 s-1 for 5 a and 0.90 cm2 V-1 s-1 for 5 b, was witnessed in single-crystalline transistors, signifying the prospects of the chiral p-helix in optoelectronic applications.

DOI 10.1002/anie.201805614
Citations Scopus - 2
2018 Xiao J-H, Zhou J, Wang Z-H, Li S-Y, Zhang W-C, Fang C-L, et al., 'Extraction of copper and zinc from naturally contaminated copper mine soils: Chemical fractionation analysis and risk assessment', JOURNAL OF CENTRAL SOUTH UNIVERSITY, 25 1274-1284 (2018) [C1]
DOI 10.1007/s11771-018-3824-6
2018 Li S, Hu S, Jiang W, Liu Y, Zhou Y, Liu J, Wang Z, 'Facile synthesis of cerium oxide nanoparticles decorated flower-like bismuth molybdate for enhanced photocatalytic activity toward organic pollutant degradation', Journal of Colloid and Interface Science, 530 171-178 (2018) [C1]
DOI 10.1016/j.jcis.2018.06.084
Citations Scopus - 9Web of Science - 7
2018 Liu X, Du X, Wang J, Duan C, Tang X, Heumueller T, et al., 'Efficient Organic Solar Cells with Extremely High Open-Circuit Voltages and Low Voltage Losses by Suppressing Nonradiative Recombination Losses', Advanced Energy Materials, 8 (2018)
DOI 10.1002/aenm.201801699
Citations Scopus - 1
2018 Ma Z, Fu H, Meng D, Jiang W, Sun Y, Wang Z, 'Isomeric N-Annulated Perylene Diimide Dimers for Organic Solar Cells', Chemistry - An Asian Journal, 13 918-923 (2018)
DOI 10.1002/asia.201800058
Citations Scopus - 2
2018 Chen S, Zhang L, Ma C, Meng D, Zhang J, Zhang G, et al., 'Alkyl Chain Regiochemistry of Benzotriazole-Based Donor Polymers Influencing Morphology and Performances of Non-Fullerene Organic Solar Cells', Advanced Energy Materials, 8 (2018)

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The effects of alkyl chain regiochemistry on the properties of donor polymers and performances of non-fullerene organic sol... [more]

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The effects of alkyl chain regiochemistry on the properties of donor polymers and performances of non-fullerene organic solar cells are investigated. Two donor polymers (PfBTAZ and PfBTAZS) are compared that have nearly identical chemical structures except for the regiochemistry of alkyl chains. The optical properties and crystallinity of two polymers are nearly identical yet the PfBTAZ:O-IDTBR blend exhibits nearly double domain size compared to the blend based on PfBTAZS:O-IDTBR. To reveal the origins of the very different domain size of two blends, the morphology of neat polymer films is characterized, and it is found that PfBTAZ tends to aggregate into much larger polymer fibers without the presence of O-IDTBR. This indicates that it is not the polymer:O-IDTBR interactions but the intrinsic aggregation properties of two polymers that determine the morphology features of neat and blend films. The stronger aggregation tendency of PfBTAZ could be explained by its more co-planar geometry of the polymer backbone arising from the different alkyl chain regiochemistry. Combined with the similar trend observed in another set of donor polymers (PTFB-P and PTFB-PS), the results provide an important understanding of the structure¿property relationships that could guide the development of donor polymers for non-fullerene organic solar cells.

DOI 10.1002/aenm.201702427
Citations Scopus - 4
2018 Feng J, Jiang W, Wang Z, 'Synthesis and Application of Rylene Imide Dyes as Organic Semiconducting Materials', Chemistry - An Asian Journal, 13 20-30 (2018)

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Rylene imide dyes have been among the most promising organic semiconducting materials for several years due to their remark... [more]

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Rylene imide dyes have been among the most promising organic semiconducting materials for several years due to their remarkable optoelectronic properties and high chemical/thermal stability. In the past decades, various excellent rylene imide dyes have been developed for optoelectronic devices, such as organic solar cells (OSCs) and organic field-effect transistors (OFETs). Recently, tremendous progress of perylene diimides (PDIs) and their analogues for use in OSCs has been achieved, which can be attributed to their ease of functionalization. In this review, we will mainly focus on the synthetic strategies toward to latest PDI dyes and higher rylene imide analogues. A variety of compounds synthesized from different building blocks are summarized, and some properties and applications are discussed.

DOI 10.1002/asia.201701424
Citations Scopus - 8
2018 Cui X, Xiao C, Winands T, Koch T, Li Y, Zhang L, et al., 'Hexacene Diimides', Journal of the American Chemical Society, 140 12175-12180 (2018)

© 2018 American Chemical Society. Acene imides are expected to possess smaller band gaps than homologous acenes while maintaining good solubility and stability. However, the desig... [more]

© 2018 American Chemical Society. Acene imides are expected to possess smaller band gaps than homologous acenes while maintaining good solubility and stability. However, the design and synthesis of large acene imides are still a big challenge. Herein, we report a one-pot synthesis of hexacene diimides (HDI) by double aromatic annulation between zirconabenzocyclopentene and tetrabrominated naphthalene diimides. HDIs with branched alkyl chains exhibit very good solubility, stability, and much smaller band gaps than hexacene. Organic field-effect transistors (OFETs) based on HDI microribbons exhibit excellent ambipolar transport behavior with the highest electron mobility of 2.17 cm2 V-1 s-1 and hole mobility of 0.30 cm2 V-1 s-1 under ambient conditions.

DOI 10.1021/jacs.8b07305
2018 Huang Y, Sheng B, Wang Z, Liu Q, Yuan R, Xiao D, Liu J, 'Deciphering the degradation/chlorination mechanisms of maleic acid in the Fe(II)/peroxymonosulfate process: An often overlooked effect of chloride', Water Research, 145 453-463 (2018)

© 2018 Elsevier Ltd In recent years, a significant effort has been devoted into investigating the effects of chloride on the degradation kinetics of aromatic pollutants. The impac... [more]

© 2018 Elsevier Ltd In recent years, a significant effort has been devoted into investigating the effects of chloride on the degradation kinetics of aromatic pollutants. The impact of chloride on the decomposition of short-chain carboxylic acid intermediates from aromatics degradation has often been overlooked. In this study the roles of chloride in the oxidation of maleic acid (MA) in the Fe(II)/peroxymonosulfate (PMS) process was investigated. Degradation efficiency, reaction intermediates, adsorbable organic halogen (AOX) accumulation and mineralization were examined. The chloride ion (Cl-) was found to have an overall negative impact on MA degradation and mineralization in the Fe(II)/PMS system. The presence of Cl- led to the formation of chlorinated by-products and a high production of AOX. The mineralization of MA was decreased with increasing Cl- concentrations. Kinetic modeling demonstrated the impact of various radicals largely depended on the concentration of Cl-. The significance of Cl2¿- or Cl2 for MA destruction was enhanced with increasing Cl- content, and overwhelmed that of SO4¿- when the Cl- concentration was over 5 mM. In the absence of Cl-, SO4¿- was the primary radical responsible for MA oxidation. A possible degradation pathway is proposed (cis-trans isomerization, decarboxylation and halogenations processes). These results may help to understand the full oxidation pathways of refractory aromatic compounds and the mechanism of chlorinated by-products formation in industrial saline wastewater treatment.

DOI 10.1016/j.watres.2018.08.055
2018 Wu Y, An C, Shi L, Yang L, Qin Y, Liang N, et al., 'The Crucial Role of Chlorinated Thiophene Orientation in Conjugated Polymers for Photovoltaic Devices', Angewandte Chemie - International Edition, 57 12911-12915 (2018)

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Chlorinated conjugated polymers not only show great potential for the realization of highly efficient polymer solar cells (... [more]

© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Chlorinated conjugated polymers not only show great potential for the realization of highly efficient polymer solar cells (PSCs) but also have simple and high-yield synthetic routes and low-cost raw materials available for their preparation. However, the study of the structure¿property relationship of chlorinated polymers is lagging. Now two chlorinated conjugated polymers, PCl(3)BDB-T and PCl(4)BDB-T are investigated. When the polymers were used to fabricate PSCs with the nonfullerene acceptor (IT-4F), surprisingly, the PCl(3)BDB-T:IT-4F-based device exhibited a negligible power conversion efficiency (PCE) of 0.18 %, while the PCl(4)BDB-T:IT-4F-based device showed an outstanding PCE of 12.33 %. These results provide new insight for the rational design and synthesis of novel chlorinated polymer donors for further improving the photovoltaic efficiencies of PSCs.

DOI 10.1002/anie.201807865
2018 Yuan R, Hu L, Yu P, Wang H, Wang Z, Fang J, 'Nanostructured Co3O4 grown on nickel foam: An efficient and readily recyclable 3D catalyst for heterogeneous peroxymonosulfate activation', CHEMOSPHERE, 198 204-215 (2018)
DOI 10.1016/j.chemosphere.2018.01.135
Citations Scopus - 9Web of Science - 5
2018 Yan C, Barlow S, Wang Z, Yan H, Jen AKY, Marder SR, Zhan X, 'Non-fullerene acceptors for organic solar cells', Nature Reviews Materials, 3 (2018)

© 2018 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Non-fullerene acceptors (NFAs) are currently a major focus of research in the development of bul... [more]

© 2018 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Non-fullerene acceptors (NFAs) are currently a major focus of research in the development of bulk-heterojunction organic solar cells (OSCs). In contrast to the widely used fullerene acceptors (FAs), the optical properties and electronic energy levels of NFAs can be readily tuned. NFA-based OSCs can also achieve greater thermal stability and photochemical stability, as well as longer device lifetimes, than their FA-based counterparts. Historically, the performance of NFA OSCs has lagged behind that of fullerene devices. However, recent developments have led to a rapid increase in power conversion efficiencies for NFA OSCs, with values now exceeding 13%, demonstrating the viability of using NFAs to replace FAs in next-generation high-performance OSCs. This Review discusses the important work that has led to this remarkable progress, focusing on the two most promising NFA classes to date: rylene diimide-based materials and materials based on fused aromatic cores with strong electron-accepting end groups. The key structure-property relationships, donor-acceptor matching criteria and aspects of device physics are discussed. Finally, we consider the remaining challenges and promising future directions for the NFA OSCs field.

DOI 10.1038/natrevmats.2018.3
Citations Scopus - 128
2018 Sheng B, Huang Y, Wang Z, Yang F, Ai L, Liu J, 'On peroxymonosulfate-based treatment of saline wastewater: When phosphate and chloride co-exist', RSC Advances, 8 13865-13870 (2018) [C1]
DOI 10.1039/c8ra00600h
2018 Yang F, Huang Y, Fang C, Xue Y, Ai L, Liu J, Wang Z, 'Peroxymonosulfate/base process in saline wastewater treatment: The fight between alkalinity and chloride ions', Chemosphere, 199 84-88 (2018) [C1]
DOI 10.1016/j.chemosphere.2018.02.023
Citations Scopus - 2Web of Science - 1
2018 Jiang B, He H, Liu Y, Tang Y, Luo S, Wang Z, 'pH-dependent roles of polycarboxylates in electron transfer between Cr(VI) and weak electron donors', Chemosphere, 197 367-374 (2018) [C1]
DOI 10.1016/j.chemosphere.2018.01.047
Citations Scopus - 3Web of Science - 1
2018 Feng J, Fu L, Huang T, Geng H, Jiang W, Wang Z, 'Rylene annulated phthalocyanine: A fully conjugated block for the construction of a supramolecular two-dimensional framework', Chemical Communications, 54 7294-7297 (2018)

© 2018 The Royal Society of Chemistry. A rylene annulated phthalocyanine (ZnPcPDI4) was designed and synthesized. Single-crystal X-ray diffraction analyses unambiguously confirmed... [more]

© 2018 The Royal Society of Chemistry. A rylene annulated phthalocyanine (ZnPcPDI4) was designed and synthesized. Single-crystal X-ray diffraction analyses unambiguously confirmed the giant molecule quasi-planar "four leaf clover" skeleton with a 27 Å diameter and a two-dimensional cage-like supramolecular structure. The fully conjugated characteristics endowed it with significant Q-band red-shifts to the near-infrared region of 785 nm, and a largely degenerated LUMO level.

DOI 10.1039/c8cc01216d
Citations Scopus - 2
2018 Yuan R, Hu L, Yu P, Wang Z, Wang H, Fang J, 'Co3O4 nanocrystals/3D nitrogen-doped graphene aerogel: A synergistic hybrid for peroxymonosulfate activation toward the degradation of organic pollutants.', Chemosphere, 210 877-888 (2018) [C1]
DOI 10.1016/j.chemosphere.2018.07.065
2018 Qian Y, Gu Y, Feng J, Jiang W, Geng Y, Duan W, et al., 'Role of Synergistic C-H···N and C-H···O H-Bonding Interactions in Self-Assemblies of a Phthalocyanine Derivative and Several Pyridine Derivatives', Journal of Physical Chemistry C, 122 24158-24163 (2018)

© 2018 American Chemical Society. Phthalocyanine (Pc)-based fused derivatives are widely used materials in many nanotechnology fields, such as photovoltaic devices, pigments, and ... [more]

© 2018 American Chemical Society. Phthalocyanine (Pc)-based fused derivatives are widely used materials in many nanotechnology fields, such as photovoltaic devices, pigments, and sensors, because of their excellent physical and chemical properties. It has been proven that most Pc molecules can self-assemble with ligands by the metal-ligand coordination interaction or p- p stacking interaction, yet little is known about the supramolecular packing of H-bonded Pc derivatives. Herein, we report the self-assembly of rylene-annulated Pc (ZnPcPDI4) with a series of pyridine derivatives at the solid/liquid interface via synergistic C-H···N and C-H···O H-bonding interactions. We use scanning tunneling microscopy combined with theoretical simulations to demonstrate the interactions in the self-assembled process. The intermolecular binding modes of Pcs with ligands and their thermodynamics stability are revealed by the combination of density functional theory and molecular dynamics simulations with the modified force field parameters. This study provides an innovative new method to build the 2D self-assembled nanostructures of Pcs by hydrogen bonds at the solid/liquid interface.

DOI 10.1021/acs.jpcc.8b07723
2018 Liang N, Sun K, Feng J, Chen Y, Meng D, Jiang W, et al., 'Near-infrared electron acceptors based on terrylene diimides for organic solar cells', Journal of Materials Chemistry A, 6 18808-18812 (2018)

© 2018 The Royal Society of Chemistry. A series of terrylene diimides (TDIs), the higher homologues of perylene diimides (PDI), were designed, synthesized and characterized in thi... [more]

© 2018 The Royal Society of Chemistry. A series of terrylene diimides (TDIs), the higher homologues of perylene diimides (PDI), were designed, synthesized and characterized in this work. In comparison to the bare TDI molecule, the bay-functionalized dyes, ph-TDI and th-TDI, possess enhanced ambipolar properties as well as organic solar cell performance.

DOI 10.1039/c8ta08186g
2018 Fu H, Wang Y, Meng D, Ma Z, Li Y, Gao F, et al., 'Suppression of recombination energy losses by decreasing the energetic offsets in perylene diimide-based nonfullerene organic solar cells', ACS Energy Letters, 3 2729-2735 (2018)

© 2018 American Chemical Society. In this work, a range of nonfullerene organic solar cells comprising two perylene diimide (PDI)-based small molecule acceptors in combination wit... [more]

© 2018 American Chemical Society. In this work, a range of nonfullerene organic solar cells comprising two perylene diimide (PDI)-based small molecule acceptors in combination with four representative polymer donors have been investigated and compared. In addition to significant differences in the power conversion efficiency, the energy losses of photovoltaic devices vary widely for these two PDI-based acceptors when paired with different donors. The sensitive Fourier-Transform photocurrent spectroscopy (FTPS) and electroluminescence (EL) measurements have been performed to quantify their respective energetic offsets (I"Eoffset) and energy losses, with the aim of understanding the distinct energy losses in the studied organic blends. By comparing these results, we find that with decreasing I"Eoffset both nonradiative recombination loss and radiative recombination loss due to the charge-Transfer state absorption are suppressed; as a result, the total energy loss is decreased. These observations offer a deep understanding of how the energetic offset affects the energy losses from the viewpoint of the Shockey-Queisser limit.

DOI 10.1021/acsenergylett.8b01665
2017 Fang C, Lou X, Huang Y, Feng M, Wang Z, Liu J, 'Monochlorophenols degradation by UV/persulfate is immune to the presence of chloride: Illusion or reality?', Chemical Engineering Journal, 323 124-133 (2017) [C1]

© 2017 Elsevier B.V.The efficiency and, accordingly, the success of the advanced oxidation processes (AOPs) has generally been evaluated on the basis of degradation kinetics. In p... [more]

© 2017 Elsevier B.V.The efficiency and, accordingly, the success of the advanced oxidation processes (AOPs) has generally been evaluated on the basis of degradation kinetics. In practice, chloride in saline wastewater is often found to inhibit degradation processes. Therefore its highly desirable to develop more effective processes which are not affected by chloride. In this study, no significant interference of chloride with monochlorophenols (MCPs, e.g. 2-CP, 3-CP and 4-CP) degradation by the UV photo-activated persulfate (UV/PS) process has been observed. This indicated the ¿illusion¿ that the UV/PS process might have been an appropriate technology working under saline conditions. To further evaluate its applicability, the generation of reaction intermediates, of adsorbable organic halogen (AOX) accumulation and of acute toxicity of MCPs in the UV/PS system were examined. In reality, several aromatic chlorinated compounds (number of chlorine atoms¿=2), such as dichlorophenols and 2,3,5,3',5'-pentachloro-biphenyl, were identified and quantified. An accumulation and relative increase of AOX with reaction time was observed in the UV/PS/Cl system. The acute toxicity tests with Photobacterium phosphoreum indicated that the inhibition effect of UV/PS reactions increased with reaction time regardless of the presence of chloride or not. The results of this study might be helpful for assessing the PS-based technologies for saline wastewater treatment.

DOI 10.1016/j.cej.2017.04.094
Citations Scopus - 14Web of Science - 13
2017 Wang Z, Sun L, Lou X, Yang F, Feng M, Liu J, 'Chemical instability of graphene oxide following exposure to highly reactive radicals in advanced oxidation processes.', JOURNAL OF COLLOID AND INTERFACE SCIENCE, 507 51-58 (2017) [C1]
DOI 10.1016/j.jcis.2017.07.105
Citations Scopus - 5Web of Science - 5
2017 Lou X, Fang C, Geng Z, Jin Y, Xiao D, Wang Z, et al., 'Significantly enhanced base activation of peroxymonosulfate by polyphosphates: Kinetics and mechanism', CHEMOSPHERE, 173 529-534 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.01.093
Citations Scopus - 9Web of Science - 7
2017 Fang C, Wang Z, Feng M, Huang Y, Yang F, Liu J, 'Trace bromide ion impurity leads to formation of chlorobromoaromatic by-products in peroxymonosulfate-based oxidation of chlorophenols', Chemosphere, 182 624-629 (2017) [C1]

© 2017 Elsevier Ltd Trace bromide (Br-) released from industrial effluents or brominated compounds is able to directly react with peroxymonosulfate (PMS) to generate a series of r... [more]

© 2017 Elsevier Ltd Trace bromide (Br-) released from industrial effluents or brominated compounds is able to directly react with peroxymonosulfate (PMS) to generate a series of reactive oxidants which can oxidize and also halogenate organics. We report the identification and evolution of by-products during 2,4,6-trichlorophenol (TCP) degradation in the presence of PMS and trace Br-. The influencing factors, including Br- concentration and pH, were investigated. The depletion of TCP was accelerated with increasing trace Br- concentration (0¿0.2¿mM) and was affected by the initial pH (3.0¿7.0). The chlorinated and brominated compounds were identified in simulated wastewater during treatment with PMS. Notably, the potential formation of chlorobromoaromatic by-products was demonstrated for the first time in the presence of PMS and trace Br-. The possible reaction pathways of TCP and its derivatives are discussed. These findings have important implications for the future applications of PMS-based oxidation processes.

DOI 10.1016/j.chemosphere.2017.05.065
Citations Scopus - 1Web of Science - 1
2017 Wang Z, Feng M, Fang C, Huang Y, Ai L, Yang F, et al., 'Both degradation and AOX accumulation are significantly enhanced in UV/peroxymonosulfate/4-chlorophenol/Cl- system: two sides of the same coin?', RSC ADVANCES, 7 12318-12321 (2017) [C1]
DOI 10.1039/c7ra01294b
Citations Scopus - 4Web of Science - 4
2017 Gao G, Liang N, Geng H, Jiang W, Fu H, Feng J, et al., 'Spiro-Fused Perylene Diimide Arrays', Journal of the American Chemical Society, 139 15914-15920 (2017)

© 2017 American Chemical Society. The straightforward palladium-catalyzed synthesis protocol toward spiro-fused perylene diimides is developed. The reaction involves two palladium... [more]

© 2017 American Chemical Society. The straightforward palladium-catalyzed synthesis protocol toward spiro-fused perylene diimides is developed. The reaction involves two palladium-catalyzed C-H activations and 4-fold C-C bond formation sequence from readily available precursors. This facile and step-economic approach also provides another convenient access to ethylene-bridged dimer (NDP) and further p-extended spiro system (SNTP). In addition, the molecular structure of spirodiperylenetetraimide (SDP) is illustrated to show a three-dimensional (3D) cruciform configuration, and its absorbance is distinctly red-shifted due to the significant spiroconjugation effect. With combined properties of broadened and intensive absorption, aligned LUMO levels, and unique molecular geometry, the spiro-fused PDI system represents a new kind of high-performance semiconducting framework as the electron acceptor in high-efficiency organic solar cells.

DOI 10.1021/jacs.7b09140
Citations Scopus - 16
2017 Fan W, Liu C, Li Y, Wang Z, 'Fluoroalkyl-modified naphthodithiophene diimides', Chemical Communications, 53 188-191 (2017)

© The Royal Society of Chemistry Two kinds of fluoroalkyl-modified naphthodithiophene diimides (NDTI) were designed and synthesized. a-Modified NDTI could form favorable slipped o... [more]

© The Royal Society of Chemistry Two kinds of fluoroalkyl-modified naphthodithiophene diimides (NDTI) were designed and synthesized. a-Modified NDTI could form favorable slipped one-dimensional (1D) stacking and N-modified NDTI shows a torsion cofacial stacking. Single-crystal transistors confirm that both fluoroalkyl-modified NDTI possess good electron transport ability with electron mobilities of 0.065 cm2V-1s-1and 1.59 cm2V-1s-1, respectively.

DOI 10.1039/c6cc07102c
Citations Scopus - 11
2017 Zhang A, Li C, Yang F, Zhang J, Wang Z, Wei Z, Li W, 'An Electron Acceptor with Porphyrin and Perylene Bisimides for Efficient Non-Fullerene Solar Cells', Angewandte Chemie - International Edition, 56 2694-2698 (2017)

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A star-shaped electron acceptor based on porphyrin as a core and perylene bisimide as end groups was constructed for applic... [more]

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A star-shaped electron acceptor based on porphyrin as a core and perylene bisimide as end groups was constructed for application in non-fullerene organic solar cells. The new conjugated molecule exhibits aligned energy levels, good electron mobility, and complementary absorption with a donor polymer. These advantages facilitate a high power conversion efficiency of 7.4 % in non-fullerene solar cells, which represents the highest photovoltaic performance based on porphyrin derivatives as the acceptor.

DOI 10.1002/anie.201612090
Citations Scopus - 84
2017 Fan W, Winands T, Doltsinis NL, Li Y, Wang Z, 'A Decatwistacene with an Overall 170° Torsion', Angewandte Chemie - International Edition, 56 15373-15377 (2017)

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Two different lengths of twistacenes, namely hexatwistacene and decatwistacene, induced by steric hindrance between imide g... [more]

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Two different lengths of twistacenes, namely hexatwistacene and decatwistacene, induced by steric hindrance between imide groups and neighboring annulated benzene rings, were synthesized by bottom-up synthesis of palladium-catalyzed Suzuki cross-coupling and C-H activation. Single-crystal X-ray analyses revealed that decatwistacene, which is the longest twistacene reported, exhibits an astonishing overall end-to-end torsion angle of about 170°, the largest torsion angle reported. Both twistacenes have an enhanced solubility and stability with respect to light and oxygen owing to their large twisting deformations together with much lower LUMO levels caused by the introduction of imide groups, opening a window to the narrowest chiral graphene nanoribbons with good stability and processability.

DOI 10.1002/anie.201709342
Citations Scopus - 5
2017 Ma Z, Xiao C, Liu C, Meng D, Jiang W, Wang Z, 'Palladium-Catalyzed Si-C Bond Formation toward Sila-Annulated Perylene Diimides', Organic Letters, 19 4331-4334 (2017)

© 2017 American Chemical Society. The first example of sila-annulation onto the perylene diimide core that allows the effective and practical synthesis of both sila- and disilaper... [more]

© 2017 American Chemical Society. The first example of sila-annulation onto the perylene diimide core that allows the effective and practical synthesis of both sila- and disilaperylene diimides (Si-PDIs and 2Si-PDIs) in one pot through palladium-catalyzed Si-C bond formation is presented. The corresponding sila-annulated perylene diimides demonstrated exceptional optical properties with noteworthy bathochromic shifts and excellent fluorescence quantum yields. Single crystal analysis revealed almost planar molecular structures and distinct packing arrangements with intense p-p interactions. Their single crystal OFET devices showed good electron mobilities of up to 0.3 cm2V-1s-1under a nitrogen atmosphere.

DOI 10.1021/acs.orglett.7b02011
Citations Scopus - 3
2017 Liang N, Meng D, Ma Z, Kan B, Meng X, Zheng Z, et al., 'Triperylene Hexaimides Based All-Small-Molecule Solar Cells with an Efficiency over 6% and Open Circuit Voltage of 1.04 V', Advanced Energy Materials, 7 (2017)

Bulk-heterojunction (BHJ) organic solar cells (OSC) containing a p-type electron donor and an n-type acceptor material have caught the attention of researchers. Numerous research ... [more]

Bulk-heterojunction (BHJ) organic solar cells (OSC) containing a p-type electron donor and an n-type acceptor material have caught the attention of researchers. Numerous research have been dedicated to the design and synthesis of novel donors and acceptors as the performance of OSC depends highly on the absorption ability energy levels and the charge transfer mobility of the donor and acceptor materials. A perylene diimide derivative with 3D rylene architecture as electron acceptor was adopted and systematically studied the effect of thermal annealing (TA) treatment on the BHJ morphology molecular packing and orientation in the BHJ active layers. Results show that the acceptor molecules triperylene hexaimides (TPH) greatly affects the molecular packing of donor DRCN5T and TA treatment has a great influence on the BHJ morphology enhancing the power conversion efficiency of DRCN5T:TPH based OSC from 0.47% to 6.16% with an open circuit voltage of 1.04 V.

DOI 10.1002/aenm.201601664
Citations Scopus - 22
2017 Gao H, Feng J, Zhang B, Xiao C, Wu Y, Kan X, et al., 'Capillary-Bridge Mediated Assembly of Conjugated Polymer Arrays toward Organic Photodetectors', Advanced Functional Materials, 27 (2017)

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Large-scale patterning of high-quality organic semiconductors is crucial for the fabrication of optoelectronic devices with... [more]

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Large-scale patterning of high-quality organic semiconductors is crucial for the fabrication of optoelectronic devices with high efficiency and low cost. Yet, owing to the uncontrollable dewetting dynamics of organic liquid in conventional solution patterning techniques, large defect density of organic architectures is inevitable, which is detrimental to the device performance. To address this challenge, herein a capillary-bridge-mediated assembly technique is developed for regulating the dewetting process, yielding large-scale 1D microstructure ordered arrays. The 1D arrays organic photodetectors exhibit a high optoelectronic performance of light on/off ratio exceeding 100, responsivity of 3.24 A W-1, detectivity of 3.20 × 1011 Jones and fast response speed, showing a great improvement compared with spin-coated membrane devices. In addition, the significant enhancement of the device photodetection under the electronic field modulation is investigated by applying a back-gate voltage and explained with the photocurrent predominating in the OFF state and the neglected thermocurrent and tunneling current promoting in the ON state of the phototransistor devices. The research offers a new insight for the facile fabrication of large-scale integrated photodetectors and other organic devices based on patterned conjugated polymers.

DOI 10.1002/adfm.201701347
Citations Scopus - 8
2017 Meng D, Fu H, Fan B, Zhang J, Li Y, Sun Y, Wang Z, 'Rigid Nonfullerene Acceptors Based on Triptycene¿Perylene Dye for Organic Solar Cells', Chemistry - An Asian Journal, 12 1286-1290 (2017)

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Three kinds of nonconjugated rigid perylene bisimide (PBI) derivatives based on a triptycene core were designed, synthesize... [more]

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Three kinds of nonconjugated rigid perylene bisimide (PBI) derivatives based on a triptycene core were designed, synthesized and characterized. The unique three-dimensional (3D) conformation of triptycene could enable formation of polymer with the favorable morphology for organic polymer solar cells (PSCs) by relieving the self-aggregation of rigid PBI units. The low-lying LUMO energy levels of these compounds demonstrated that they are very suitable for use as acceptors in organic solar cells. A higher power conversion efficiency (PCE) of 6.15 % was obtained for the blend film using the compound with two PBI units (T-2) as the acceptor and commercial poly[[4,8-bis[5-(2-ethylhexyl)thiophene-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophenediyl]] (PCE-10) as the electron donor.

DOI 10.1002/asia.201700440
Citations Scopus - 5
2017 Wei J, Meng D, Zhang L, Wang Z, 'Lateral Extension of a Benzodithiophene System: Construction of Heteroacenes Containing Various Chalcogens', Chemistry - An Asian Journal, 12 1879-1882 (2017)

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A series of linear acenes with five fused rings, which contain thiophene, selenophene, and tellurophene as the outmost ring... [more]

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim A series of linear acenes with five fused rings, which contain thiophene, selenophene, and tellurophene as the outmost rings, have been synthesized from well-known benzodithiophene (BDT). It was found that the optical, electrochemical properties and crystal packing motifs could be modulated by changing heteroatoms in the outmost rings.

DOI 10.1002/asia.201700552
Citations Scopus - 1
2017 Xin R, Feng J, Zeng C, Jiang W, Zhang L, Meng D, et al., 'Nonfullerene-acceptor all-small-molecule organic solar cells based on highly twisted perylene bisimide with an efficiency of over 6%', ACS Applied Materials and Interfaces, 9 2739-2746 (2017)

© 2016 American Chemical Society. Two twisted singly linked perylene bisimide (PBI) dimers with chalcogen bridges in the PBI cores, named C4,4-SdiPBI-S and C4,4-SdiPBI-Se, were sy... [more]

© 2016 American Chemical Society. Two twisted singly linked perylene bisimide (PBI) dimers with chalcogen bridges in the PBI cores, named C4,4-SdiPBI-S and C4,4-SdiPBI-Se, were synthesized as acceptors for nonfullerene all-small-molecule organic solar cells (NF all-SMSCs). A moderate-band-gap small-molecule DR3TBDTT used as the electron donor displayed complementary absorption with C4,4-SdiPBI-S and C4,4-SdiPBI-Se. It was found that solvent-vapor annealing (SVA) played a critical role in the photovoltaic performance in NF all-SMSCs, which improves the crystallinity of the donor and acceptors, promotes the proper phase segregation domain size, and therefore enhances charge transport. The power conversion efficiencies (PCEs) of NF all-SMSC devices based on DR3TBDTT/C4,4-SdiPBI-S and DR3TBDTT/C4,4-SdiPBI-Se increased from 2.52% to 5.81% (JSC = 11.12 mA cm-2, VOC = 0.91 V, and FF = 57.32%) and from 2.65% to 6.22% (JSC = 11.55 mA cm-2, VOC = 0.92 V, and FF = 58.72%), respectively, after exposure to chloroform vapor. The best efficiency of 6.22% is one of the highest PCEs for NF all-SMSC-based PBI acceptors so far. The studies illustrate that highly efficient NF all-SMSCs can be achieved by using a PBI acceptor with a suitable SVA process.

DOI 10.1021/acsami.6b13721
Citations Scopus - 13
2017 Wu W, Xiang H, Fan W, Wang J, Wang H, Hua X, et al., 'Cosensitized Porphyrin System for High-Performance Solar Cells with TOF-SIMS Analysis', ACS Applied Materials and Interfaces, 9 16081-16090 (2017)

© 2017 American Chemical Society. To date, development of organic sensitizers has been predominately focused on light harvesting, highest occupied molecular orbital and lowest uno... [more]

© 2017 American Chemical Society. To date, development of organic sensitizers has been predominately focused on light harvesting, highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels, and the electron transferring process. In contrast, their adsorption mode as well as the dynamic loading behavior onto nanoporous TiO2 is rarely considered. Herein, we have employed the time-of-flight secondary ion mass spectrometry (TOF-SIMS) to gain insight into the competitive dye adsorption mode and kinetics in the cosensitized porphyrin system. Using novel porphyrin dye FW-1 and D-A-p-A featured dye WS-5, the different bond-breaking mode in TOF-SIMS and dynamic dye-loading amount during the coadsorption process are well-compared with two different anchoring groups, such as benzoic acid and cyanoacrylic acid. With the bombardment mode in TOF-SIMS spectra, we have speculated that the cyano group grafts onto nanoporous TiO2 as tridentate binding for the common anchoring unit of cyanoacrylic acid and confirmed it through extensive first-principles density functional theory calculation by anchoring either the carboxyl or cyano group, which shows that the cyano group can efficiently participate in the adsorption of the WS-5 molecule onto the TiO2 nanocrystal. The grafting reinforcement interaction between the cyano group and TiO2 in WS-5 can well-explain the rapid adsorption characteristics. A strong coordinate bond between the lone pair of electrons on the nitrogen or oxygen atom and the Lewis acid sites of TiO2 can increase electron injection efficiencies with respect to those from the bond between the benzoic acid group and the Brønsted acid sites of the TiO2 surface. Upon optimization of the coadsorption process with dye WS-5, the photoelectric conversion efficiency based on porphyrin dye FW-1 is increased from 6.14 to 9.72%. The study on the adsorption dynamics of organic sensitizers with TOF-SIMS analysis might provide a new venue for improvement of cosensitized solar cells.

DOI 10.1021/acsami.7b00281
Citations Scopus - 3
2017 Fu H, Meng D, Meng X, Sun X, Huo L, Fan Y, et al., 'Influence of alkyl chains on photovoltaic properties of 3D rylene propeller electron acceptors', Journal of Materials Chemistry A, 5 3475-3482 (2017)

© The Royal Society of Chemistry. A series of propeller-shaped triperylene hexaimide (TPH) non-fullerene acceptors, featuring branched alkyl side chains with different lengths (TP... [more]

© The Royal Society of Chemistry. A series of propeller-shaped triperylene hexaimide (TPH) non-fullerene acceptors, featuring branched alkyl side chains with different lengths (TPH-4, TPH-5, TPH-6, and TPH-7), have been designed and synthesized. The effects of the branched alkyl chain length on the physical properties, thin-film microstructure, molecular packing, charge transport and the resulting photovoltaic properties of these materials have been systematically investigated. It was found that TPH-7 with the longest alkyl side chain showed the best photovoltaic performance compared with three other TPH molecules, and an outstanding power conversion efficiency (PCE) of 8.6% under AM 1.5G irradiation (100 mW cm-2) has been obtained using a wide-band-gap polymer PDBT-T1 as the electron donor. These results demonstrate that finely tailoring alkyl substituents on TPH-based small molecular acceptors critically impacts the structural order of thin films and molecular orientation, and thus the photovoltaic performance.

DOI 10.1039/c6ta09049d
Citations Scopus - 12
2017 Xiao C, Kan X, Liu C, Jiang W, Zhao G, Zhao Q, et al., 'Controlled formation of large-area single-crystalline TIPS-pentacene arrays through superhydrophobic micropillar flow-coating', Journal of Materials Chemistry C, 5 2702-2707 (2017)

© The Royal Society of Chemistry. A convenient and controlled organic semiconductor alignment strategy, superhydrophobic micropillar flow-coating (SMFC), is presented. Patterned, ... [more]

© The Royal Society of Chemistry. A convenient and controlled organic semiconductor alignment strategy, superhydrophobic micropillar flow-coating (SMFC), is presented. Patterned, large-area (>1 cm2) 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) single-crystalline arrays which show hole mobilities up to 6.8 cm2V-1s-1were obtained via this method. Crucially, the polymorphism of TIPS-pentacene was regulated by tuning the flow rate, solvent and the substrate hydrophobicity. These results indicate that this technique is reliable for creating uniform and homogenous organic single-crystalline arrays with controlled crystal packing, thickness, and position.

DOI 10.1039/c6tc04704a
Citations Scopus - 9
2017 Ben HJ, Ren XK, Song B, Li X, Feng Y, Jiang W, et al., 'Synthesis, crystal structure, enhanced photoluminescence properties and fluoride detection ability of S-heterocyclic annulated perylene diimide-polyhedral oligosilsesquioxane dye', Journal of Materials Chemistry C, 5 2566-2576 (2017)

© The Royal Society of Chemistry. A novel S-heterocyclic annulated perylene diimide (SPDI) derivative connected to two polyhedral oligosilsesquioxane (POSS) nanoparticles was desi... [more]

© The Royal Society of Chemistry. A novel S-heterocyclic annulated perylene diimide (SPDI) derivative connected to two polyhedral oligosilsesquioxane (POSS) nanoparticles was designed and synthesized to reveal the effect of bulky substituent groups on its self-assembly behavior and photoluminescence properties. This featured organic-inorganic hybrid can easily self-assemble into crystalline microbelts with a length of several hundred micrometers. The phase behavior and crystal structure of the compound was then elucidated via a combination of different experimental techniques such as differential scanning calorimetry (DSC), one- and two-dimensional (1D and 2D) X-ray diffraction (XRD), UV/Vis and fluorescence spectra, and tandem mass spectrometry with traveling wave ion mobility separation. The experimental results reveal that the compound has a strong propensity to form a dimer in solution and possesses unique molecular packing of discrete dimeric motifs in the solid state. Moreover, due to this discrete molecular packing behavior, the compound exhibits enhanced photoluminescence properties both in solution and in the solid state compared to the reference compound SPDI without a pendant POSS cage. In addition, based on the dual reactions of electron transfer and fluoride-triggered Si-O bond cleavage, the POSS containing SPDI exhibits higher selectivity and sensitivity to fluoride anions, and a quicker response against the reference SPDI without a pendant POSS cage. The enhanced luminescence properties, and the ability to form ultralong crystalline microbelts, in combination with the rapid selective response for F- make this compound a promising material for the fabrication of luminescent devices and colorimetric chemosensors.

DOI 10.1039/C6TC05171E
Citations Scopus - 11
2017 Feng J, Liang N, Jiang W, Meng D, Xin R, Xu B, et al., 'Twisted terrylene dyes: Synthesis and application in organic solar cells', Organic Chemistry Frontiers, 4 811-816 (2017)

© 2017 the Partner Organisations. Two twisted terrylene diimides (TDIs), namely TDI2 and BTDI3, have been designed and synthesized. In comparison to monomeric TDI, their molecular... [more]

© 2017 the Partner Organisations. Two twisted terrylene diimides (TDIs), namely TDI2 and BTDI3, have been designed and synthesized. In comparison to monomeric TDI, their molecular geometries and optoelectronic properties have been systematically investigated. BTDI3, with a highly twisted 3D geometry, shows the best light-absorbing capability in the range of 500-700 nm and a suitable LUMO level. Simultaneously, a preliminary exploration of their photovoltaic performances was carried out. The optimized device based on PBDT-TS1/BTDI3 produces a power conversion efficiency (PCE) of 3.64%, demonstrating the potential of terrylene dyes in the photovoltaics field.

DOI 10.1039/c7qo00118e
Citations Scopus - 5
2017 Huang Y, Wang Z, Liu Q, Wang X, Yuan Z, Liu J, 'Effects of chloride on PMS-based pollutant degradation: A substantial discrepancy between dyes and their common decomposition intermediate (phthalic acid)', Chemosphere, 187 338-346 (2017) [C1]

© 2017 Elsevier Ltd A considerable effort has been devoted to elucidating the roles of chloride in oxidative degradation and chlorination of dyes. However, few investigations are ... [more]

© 2017 Elsevier Ltd A considerable effort has been devoted to elucidating the roles of chloride in oxidative degradation and chlorination of dyes. However, few investigations are available on kinetic analysis and transformation pathways of secondary degradation byproducts of dyes in saline wastewater treatment. Here the impact of chlorine on the degradation rate of phthalic acid, a typical dye degradation intermediate, by the Co2+/peroxymonosulfate (PMS) process was examined. Degradation efficiency, intermediate products, AOX (adsorbable organic halogen) formation and mineralization were considered. An overall negative impact was observed within the concentration of Cl-up to 100 mM, differing from the dual effect of chloride on dye degradation process as previously observed. The presence of high levels of Cl-led to a low production of AOX and a reduction of the formation of chlorinated by-products. The mineralization was also restrained when the Cl-concentration was increased. Degradation pathways for these processes are proposed. These findings provide valuable information about the degradation pathways of dyes and about the formation mechanism of chlorinated by-products in industrial saline wastewater treatment.

DOI 10.1016/j.chemosphere.2017.08.120
Citations Scopus - 2Web of Science - 1
2017 Li S, Hu S, Jiang W, Liu Y, Liu J, Wang Z, 'Synthesis of n-type TaON microspheres decorated by p-type Ag
DOI 10.1016/j.mcat.2017.03.027
Citations Scopus - 16Web of Science - 15
2017 Liang N, Jiang W, Hou J, Wang Z, 'New developments in non-fullerene small molecule acceptors for polymer solar cells', Materials Chemistry Frontiers, 1 1291-1303 (2017)

© 2017 the Partner Organisations. During the past two years, non-fullerene electron acceptors for organic solar cells have attracted considerable attention. Significant progress h... [more]

© 2017 the Partner Organisations. During the past two years, non-fullerene electron acceptors for organic solar cells have attracted considerable attention. Significant progress has been made in that the power conversion efficiency of polymer solar cells based on non-fullerene small molecule acceptors now exceeds 12%, exhibiting many advantages over their fullerene counterparts. One of the greatest strengths for NFAs is their tunability via chemical modulation to fine-tune their absorption, energy level and electronic mobility, which is difficult to achieve with fullerene derivatives. This review describes very recent developments of polymer donor:small molecular non-fullerene acceptors in several systems since 2015, including rylene imide, indacenodithiophene and diketopyrrolopyrrole-based small molecular acceptors. Molecular design considerations and structure-property relationships are also discussed.

DOI 10.1039/c6qm00247a
Citations Scopus - 76
2017 Li S, Hu S, Jiang W, Liu Y, Liu J, Wang Z, 'Facile synthesis of flower-like Ag3VO4/Bi2WO6 heterojunction with enhanced visible-light photocatalytic activity', Journal of Colloid and Interface Science, 501 156-163 (2017) [C1]
DOI 10.1016/j.jcis.2017.04.057
Citations Scopus - 43Web of Science - 40
2017 Choppala G, Bush R, Moon E, Ward N, Wang Z, Bolan N, Sullivan L, 'Oxidative transformation of iron monosulfides and pyrite in estuarine sediments: Implications for trace metals mobilisation', Journal of Environmental Management, 186 158-166 (2017) [C1]
DOI 10.1016/j.jenvman.2016.06.062
Citations Scopus - 2Web of Science - 2
Co-authors Nanthi Bolan, Richard Bush
2017 Wang Z, Ai L, Huang Y, Zhang J, Li S, Chen J, Yang F, 'Degradation of azo dye with activated peroxygens: When zero-valent iron meets chloride', RSC Advances, 7 30941-30948 (2017) [C1]
DOI 10.1039/c7ra03872k
Citations Scopus - 8Web of Science - 8
2017 Huang Y, Yang F, Ai L, Feng M, Wang C, Wang Z, Liu J, 'On the kinetics of organic pollutant degradation with Co2+/peroxymonosulfate process: When ammonium meets chloride', CHEMOSPHERE, 179 331-336 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.03.110
Citations Scopus - 6Web of Science - 6
2017 Wang Z, Sun H, 'Nanoscale in Photocatalysis', NANOMATERIALS, 7 (2017)
DOI 10.3390/nano7040086
2017 Xiang H, Fan W, Li JH, Li T, Robertson N, Song X, et al., 'High-Performance Porphyrin-Based Dye-Sensitized Solar Cells with Iodine and Cobalt Redox Shuttles', ChemSusChem, 10 938-945 (2017)

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Recently, enormous research passion has been devoted to enhance the power conversion efficiency (PCE) of porphyrin sensitiz... [more]

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Recently, enormous research passion has been devoted to enhance the power conversion efficiency (PCE) of porphyrin sensitizers for dye-sensitized solar cells (DSSCs), but the major stumbling block is the absorption defect in the visible-light region. To address this challenge, high-performance DSSCs are reported based on a new donor¿p¿acceptor sensitizer FW-1, 7H-dibenzo[c,g]carbazole-substituted and fused zinc porphyrin, co-sensitized with a benzotriazole-containing dye (WS-5) in iodine and cobalt redox systems, and high PCEs of 10.21 and 10.42 %, respectively, were obtained. An unprecedented breakthrough was obtained by making one sensitizer suitable for several electrolyte systems because of its appropriate molecular orbitals and co-sensitizer.

DOI 10.1002/cssc.201601617
Citations Scopus - 3
2017 Li S, Hu S, Xu K, Jiang W, Liu J, Wang Z, 'A Novel Heterostructure of BiOI Nanosheets Anchored onto MWCNTs with Excellent Visible-Light Photocatalytic Activity', NANOMATERIALS, 7 (2017) [C1]
DOI 10.3390/nano7010022
Citations Scopus - 17Web of Science - 12
2016 Cui X, Xiao C, Zhang L, Li Y, Wang Z, 'Polycyclic aromatic hydrocarbons with orthogonal tetraimides as n-type semiconductors', Chemical Communications, 52 13209-13212 (2016)

© 2016 The Royal Society of Chemistry. Two new polycyclic aromatic hydrocarbons with orthogonal imide groups have been synthesized and characterized. These semiconductors have str... [more]

© 2016 The Royal Society of Chemistry. Two new polycyclic aromatic hydrocarbons with orthogonal imide groups have been synthesized and characterized. These semiconductors have strong electron affinities with an electron mobility of up to 1.75 cm2V-1s-1in solution-processed single-crystalline microfibers.

DOI 10.1039/c6cc06486h
Citations Scopus - 14
2016 Meng D, Sun D, Zhong C, Liu T, Fan B, Huo L, et al., 'High-Performance Solution-Processed Non-Fullerene Organic Solar Cells Based on Selenophene-Containing Perylene Bisimide Acceptor', Journal of the American Chemical Society, 138 375-380 (2016)

© 2015 American Chemical Society. Non-fullerene acceptors have recently attracted tremendous interest because of their potential as alternatives to fullerene derivatives in bulk h... [more]

© 2015 American Chemical Society. Non-fullerene acceptors have recently attracted tremendous interest because of their potential as alternatives to fullerene derivatives in bulk heterojunction organic solar cells. However, the power conversion efficiencies (PCEs) have lagged far behind those of the polymer/fullerene system, mainly because of the low fill factor (FF) and photocurrent. Here we report a novel perylene bisimide (PBI) acceptor, SdiPBI-Se, in which selenium atoms were introduced into the perylene core. With a well-established wide-band-gap polymer (PDBT-T1) as the donor, a high efficiency of 8.4% with an unprecedented high FF of 70.2% is achieved for solution-processed non-fullerene organic solar cells. Efficient photon absorption, high and balanced charge carrier mobility, and ultrafast charge generation processes in PDBT-T1:SdiPBI-Se films account for the high photovoltaic performance. Our results suggest that non-fullerene acceptors have enormous potential to rival or even surpass the performance of their fullerene counterparts.

DOI 10.1021/jacs.5b11149
Citations Scopus - 362
2016 Meng D, Fu H, Xiao C, Meng X, Winands T, Ma W, et al., 'Three-Bladed Rylene Propellers with Three-Dimensional Network Assembly for Organic Electronics', Journal of the American Chemical Society, 138 10184-10190 (2016)

© 2016 American Chemical Society. Two kinds of conjugated C3-symmetric perylene dyes, namely, triperylene hexaimides (TPH) and selenium-annulated triperylene hexaimides (TPH-Se), ... [more]

© 2016 American Chemical Society. Two kinds of conjugated C3-symmetric perylene dyes, namely, triperylene hexaimides (TPH) and selenium-annulated triperylene hexaimides (TPH-Se), are efficiently synthesized. Both TPH and TPH-Se have broad and strong absorption in the region 300-600 nm together with suitable LUMO levels of about -3.8 eV. Single-crystal X-ray diffraction studies show that TPH displays an extremely twisted three-bladed propeller configuration and a unique 3D network assembly in which three PBI subunits in one TPH molecule have strong p-p intermolecular interactions with PBI subunits in neighboring molecules. The integration of selenophene to TPH endows TPH-Se with a more distorted propeller configuration and a more compact 3D network assembly due to the Se···O interactions. A single-crystal transistor confirms that both TPH and TPH-Se possess good electron-transport ability. TPH and TPH-Se acceptor-based solar cells show high power conversion efficiency of 8.28% and 9.28%, respectively, which mainly results from the combined properties of broad and strong absorption ability, appropriate LUMO level, desirable aggregation, high electron mobility, and good film morphology with the polymer donor.

DOI 10.1021/jacs.6b04368
Citations Scopus - 190
2016 Zhang A, Xiao C, Wu Y, Li C, Ji Y, Li L, et al., 'Effect of Fluorination on Molecular Orientation of Conjugated Polymers in High Performance Field-Effect Transistors', Macromolecules, 49 6431-6438 (2016)

© 2016 American Chemical Society. Fluorinated conjugated polymers have been widely used in high performance polymer solar cells, but they showed limited application in field-effec... [more]

© 2016 American Chemical Society. Fluorinated conjugated polymers have been widely used in high performance polymer solar cells, but they showed limited application in field-effect transistors (FETs). In this paper, we focus on the influence of fluorine atoms upon charge transport of conjugated polymers in FET devices. Two series of conjugated polymers without or with fluorine atoms were designed and applied into FETs. Nonfluorinated conjugated polymers show high hole mobilties up to 11.16 cm2V-1s-1, while fluorinated polymers exhibit low hole mobilities below 1.80 cm2V-1s-1. Further investigation by differential scanning calorimetry (DSC) and 2D grazing-incidence wide-angle X-ray scattering (2D-GIWAXS) reveal that fluorinated conjugated polymers show low crystallinity and "face-on" orientation in thin films, explaining their poor hole mobilities in FET devices. Our results clearly show how the chemical structures influence the charge transport properties, which can be used to design new conjugated polymers toward high performance FETs.

DOI 10.1021/acs.macromol.6b01446
Citations Scopus - 18
2016 Ji Y, Xiao C, Heintges GHL, Wu Y, Janssen RAJ, Zhang D, et al., 'Conjugated polymer with ternary electron-deficient units for ambipolar nanowire field-effect transistors', Journal of Polymer Science, Part A: Polymer Chemistry, 54 34-38 (2016)

© 2015 Wiley Periodicals, Inc. A small band gap conjugated polymer with ternary acceptors of diketopyrrolopyrrole, benzothiadiazole, and naphthalenediimde is presented. Nanowires ... [more]

© 2015 Wiley Periodicals, Inc. A small band gap conjugated polymer with ternary acceptors of diketopyrrolopyrrole, benzothiadiazole, and naphthalenediimde is presented. Nanowires of this polymer were fabricated to show ambipolar field-effect transistors with hole and electron mobilities of 1.61 and 0.98 cm2 V-1 s-1.

DOI 10.1002/pola.27898
Citations Scopus - 13
2016 Ji Y, Xiao C, Wang Q, Zhang J, Li C, Wu Y, et al., 'Asymmetric Diketopyrrolopyrrole Conjugated Polymers for Field-Effect Transistors and Polymer Solar Cells Processed from a Nonchlorinated Solvent', Advanced Materials, 28 943-950 (2016)

Copyright © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Newly designed asymmetric diketopyrrolopyrrole conjugated polymers with two different aromatic substituents possess a hole... [more]

Copyright © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Newly designed asymmetric diketopyrrolopyrrole conjugated polymers with two different aromatic substituents possess a hole mobility of 12.5 cm2V-1s-1in field-effect transistors and a power conversion efficiency of 6.5% in polymer solar cells, when solution processed from a nonchlorinated toluene/diphenyl ether mixed solvent.

DOI 10.1002/adma.201504272
Citations Scopus - 73
2016 Zhu B, Wang H, Liu Y, Qi D, Liu Z, Wang H, et al., 'Skin-Inspired Haptic Memory Arrays with an Electrically Reconfigurable Architecture', Advanced Materials, 28 1559-1566 (2016)

© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Skin-inspired haptic-memory devices, which can retain pressure information after the removel of external pressure by virtu... [more]

© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Skin-inspired haptic-memory devices, which can retain pressure information after the removel of external pressure by virtue of the nonvolatile nature of the memory devices, are achieved. The rise of haptic-memory devices will allow for mimicry of human sensory memory, opening new avenues for the design of next-generation high-performance sensing devices and systems.

DOI 10.1002/adma.201504754
Citations Scopus - 47
2016 Liu T, Guo Y, Yi Y, Huo L, Xue X, Sun X, et al., 'Ternary Organic Solar Cells Based on Two Compatible Nonfullerene Acceptors with Power Conversion Efficiency >10%', Advanced Materials, 28 10008-10015 (2016)

High-efficiency ternary organic solar cells using two different nonfullerene acceptors (ITIC-Th and SdiPBI-Se) and one conjugated copolymer (PDBT-T1) were demonstrated. Solar cell... [more]

High-efficiency ternary organic solar cells using two different nonfullerene acceptors (ITIC-Th and SdiPBI-Se) and one conjugated copolymer (PDBT-T1) were demonstrated. Solar cells based on PDBT-T1:SdiPBI-Se:ITIC-Th ternary blend with various ITIC-Th contents are fabricated. The overall ratio of donor to acceptor ratio is kept at 1:1 in this study. The composition of SdiPBI-Se:ITIC-Th varies as a handle to manipulate absorption, morphology, and performance. In fabrication, a small amount of diioctane (0.7% DIO) is used to optimize the morphology of the active layer. However, solar cells fabricated with PDBT-T1:ITIC-Th binary blend show a much lower PCE (6.43%) than the literature results, mainly because of using different host solvent and additive. The high PCE arose mainly from the dramatically increased photocurrent. The morphological study shows that SdiPBI-Se and ITIC-Th are miscible, with reduced crystallinity while maintaining good transport features. The MD simulations indicate that the stronger tendency of binding between ITIC-Th and SdiPBI-Se, agreeing well with the experimental results. The high efficiency of 10.3% is one of the highest values reported for nonfullerene organic solar cells.

DOI 10.1002/adma.201602570
Citations Scopus - 118
2016 Liu L, Ren Z, Xiao C, He B, Dong H, Yan S, et al., 'Epitaxially-crystallized oriented naphthalene bis(dicarboximide) morphology for significant performance improvement of electron-transporting thin-film transistors', Chemical Communications, 52 4902-4905 (2016)

© The Royal Society of Chemistry 2016. Large-area highly-ordered F-NDI films were obtained by epitaxial-crystallization on highly-oriented PE substrates through vacuum deposition.... [more]

© The Royal Society of Chemistry 2016. Large-area highly-ordered F-NDI films were obtained by epitaxial-crystallization on highly-oriented PE substrates through vacuum deposition. An electron mobility of 0.2 cm2V-1s-1was achieved based on such epitaxially-crystallized F-NDI films, which is 4 times higher than that of its un-oriented thin film devices.

DOI 10.1039/c6cc01148a
Citations Scopus - 12
2016 Fan W, Liang N, Meng D, Feng J, Li Y, Hou J, Wang Z, 'A high performance three-dimensional thiophene-annulated perylene dye as an acceptor for organic solar cells', Chemical Communications, 52 11500-11503 (2016)

© The Royal Society of Chemistry 2016. A high performance three-dimensional (3D) thiophene-annulated perylene dye, namely tetra-PBI-S, was designed and synthesized. The appropriat... [more]

© The Royal Society of Chemistry 2016. A high performance three-dimensional (3D) thiophene-annulated perylene dye, namely tetra-PBI-S, was designed and synthesized. The appropriate LUMO level, balanced carrier mobilities and favourable phase separation make tetra-PBI-S based solar cells show a much higher power conversion efficiency (PCE) of 6.2% than tetra-PBI based solar cells with a PCE of 3.6%.

DOI 10.1039/c6cc05810h
Citations Scopus - 16
2016 Winands T, Böckmann M, Schemme T, Ly PMT, De Jong DH, Wang Z, et al., 'P3HT:DiPBI bulk heterojunction solar cells: Morphology and electronic structure probed by multiscale simulation and UV/vis spectroscopy', Physical Chemistry Chemical Physics, 18 6217-6227 (2016)

© 2016 the Owner Societies. Coarse grained molecular dynamics simulations are performed for a mixture of poly(3-hexylthiophene) (P3HT) and diperylene bisimide (DiPBI). The effect ... [more]

© 2016 the Owner Societies. Coarse grained molecular dynamics simulations are performed for a mixture of poly(3-hexylthiophene) (P3HT) and diperylene bisimide (DiPBI). The effect of different annealing and cooling protocols on the morphology is investigated and the resulting domain structures are analyzed. In particular, p-stacked clusters of DiPBI molecules are observed whose size decreases with increasing temperature. Domain structure and diffusivity data suggest that the DiPBI subsystem undergoes an order ¿ disorder phase transition between 700 and 900 K. Electronic structure calculations based on density functional theory are carried out after backmapping the coarse grained model onto an atomistic force field representation built upon first principles. UV/vis absorption spectra of the P3HT:DiPBI mixture are computed using time-dependent density functional linear response theory and recorded experimentally for a spin-coated thin film. It is demonstrated that the absorption spectrum depends sensitively on the details of the amorphous structure, thus providing valuable insight into the morphology. In particular, the results show that the tempering procedure has a significant influence on the material's electronic properties. This knowledge may help to develop effective processing routines to enhance the performance of bulk heterojunction solar cells.

DOI 10.1039/c5cp06704a
Citations Scopus - 8
2016 Li C, Lin Z, Li Y, Wang Z, 'Synthesis and Applications of p-Extended Naphthalene Diimides', Chemical Record, 16 873-885 (2016)

© 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Naphthalene diimides have received much attention due to their high electron affinit... [more]

© 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Naphthalene diimides have received much attention due to their high electron affinities, high electron mobility, and good thermal and oxidative stability, therefore making them promising candidates for a variety of organic electronic applications. However, p-extended naphthalene diimides with lower HOMO-LUMO gaps and higher stability have only been developed recently because of the synthetic difficulties. This account describes recent developments in the structures, synthesis, properties, and applications of p-extended naphthalene diimides, including pure-carbon and heterocyclic acene diimides, from our research group.

DOI 10.1002/tcr.201500246
Citations Scopus - 6
2016 Liu L, Ren Z, Xiao C, Dong H, Yan S, Hu W, Wang Z, 'Surface-induced highly oriented perylo[1,12-b,c,d]selenophene thin films for high performance organic field-effect transistors', Organic Electronics: physics, materials, applications, 35 186-192 (2016)

© 2016 Elsevier B.V. Epitaxial crystallization of perylo[1,12-b,c,d]selenophene (PESE) on highly oriented polyethylene (PE) substrate through vapor phase deposition has been achie... [more]

© 2016 Elsevier B.V. Epitaxial crystallization of perylo[1,12-b,c,d]selenophene (PESE) on highly oriented polyethylene (PE) substrate through vapor phase deposition has been achieved. Oriented PESE crystals with different crystalline morphologies can be fabricated by changing the temperature of PE substrate during vacuum evaporation. When the PE substrate temperature is lower than 70 °C, sparsely dispersed PESE lathlike crystals are produced with their long axis preferentially aligned perpendicular to the chain direction of PE crystals. While the close films of PESE with lathlike crystals aligned with long axis parallel to the chain direction of PE film were obtained above 90 °C. Transistors based on expitaxially crystallized PESE films have been fabricated and the transistor properties were also studied. It is found that transistors show different electrical characteristics depending on the preparation conditions of expitaxially crystallized PESE films. The transistors based on the PESE/PE-SiO2/Si with PESE deposited on oriented PE film at low temperature, i.e.; <70 °C, display a similar poor properties with the PESE/OTS-SiO2/Si type transistors. However, when the deposition temperature was elevated to 90 °C, the transistors exhibit a maximum field-effect mobility of 4.4 × 10-2 cm2 V-1 s-1 and maximum on/off ratio of 2.0 × 105, which are about 2 orders of magnitudes higher than the PESE/OTS-SiO2/Si based transistors.

DOI 10.1016/j.orgel.2016.05.017
Citations Scopus - 5
2016 Liang N, Sun K, Zheng Z, Yao H, Gao G, Meng X, et al., 'Perylene Diimide Trimers Based Bulk Heterojunction Organic Solar Cells with Efficiency over 7%', Advanced Energy Materials, 6 (2016)
DOI 10.1002/aenm.201600060
Citations Scopus - 59
2016 Fan B, Meng D, Peng D, Lin S, Wang Z, Sun Y, 'Perylene Bisimides as efficient electron transport layers in planar heterojunction perovskite solar cells', Science China Chemistry, 59 1658-1662 (2016)

© 2016, Science China Press and Springer-Verlag Berlin Heidelberg. Two perylene bisimides based non-fullerene small molecules, H-DIPBI and B-DIPBI, are applied into inverted plana... [more]

© 2016, Science China Press and Springer-Verlag Berlin Heidelberg. Two perylene bisimides based non-fullerene small molecules, H-DIPBI and B-DIPBI, are applied into inverted planar heterojunction perovskite solar cells. The power conversion efficiency up to 11.6% has been achieved for device with B-DIPBI, indicating that non-fullerene acceptor can function as the electron transport layer to replace PCBM in perovskite solar cells.

DOI 10.1007/s11426-016-0147-0
Citations Scopus - 7
2016 Feng G, Xu Y, Xiao C, Zhang J, Zhang X, Li C, et al., 'Poly(pentacyclic lactam-alt-diketopyrrolopyrrole) for field-effect transistors and polymer solar cells processed from non-chlorinated solvents', Polymer Chemistry, 7 164-170 (2016)

© 2015 The Royal Society of Chemistry. A semi-crystalline conjugated polymer based on two electron-deficient units, pentacyclic lactam (PCL) and diketopyrrolopyrrole (DPP), was de... [more]

© 2015 The Royal Society of Chemistry. A semi-crystalline conjugated polymer based on two electron-deficient units, pentacyclic lactam (PCL) and diketopyrrolopyrrole (DPP), was designed and synthesized for application in field-effect transistors (FETs) and polymer solar cells (PSCs). The polymer has a high molecular weight, near-infrared absorption up to 900 nm and good solubility in toluene. When the polymer thin films were solution-processed from toluene with diphenyl ether as an additive, the FET devices achieved a high hole mobility of 0.81 cm2 V-1 s-1. With the same solution-processing solvents, bulk-heterojunction solar cells based on this polymer as an electron donor provided a power conversion efficiency of 4.7% with an optimal energy loss of 0.65 eV due to its deep lowest unoccupied molecular orbital level. Further study on the morphology of the pure polymer or blend thin films by atomic force microscopy, transmission electron microscopy and 2D grazing-incidence wide-angle X-ray scattering reveals that the new polymer has good crystalline property, which is mainly due to the coplanar nature of the conjugated backbone. This work demonstrates that conjugated polymers incorporating several electron-deficient units can be potentially used in high performance FETs and PSCs.

DOI 10.1039/c5py01406a
Citations Scopus - 8
2016 Lin Z, Li C, Meng D, Li Y, Wang Z, 'Hybrid Corannulene¿Perylene Dyes: Facile Synthesis and Optoelectronic Properties', Chemistry - An Asian Journal, 11 2695-2699 (2016)

© 2016 Wiley-VCH Verlag GmbH &amp; Co. KGaA, Weinheim Considering the peculiar topology of corannulene and extraordinary optoelectronic properties of perylene dyes, a series of ... [more]

© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Considering the peculiar topology of corannulene and extraordinary optoelectronic properties of perylene dyes, a series of hybrid corannulene¿perylene dyes, namely corannulene-fused perylene-3,4-dicarboxylic acid monoimide (PMI) and corannulene-fused perylene-3,4,9,10-tetracarboxylic acid diimides (PDIs), were efficiently synthesized by a Suzuki coupling (carbon¿carbon bond formation) and subsequent oxidative cyclization and photocyclization, respectively. Single crystal packing demonstrates that the solid state of the corannulene-fused PMI is arranged in back to back antiparallel dimers due to the strong dipole¿dipole interactions. Integration of the corannulene unit to the perylene dyes along peri-positions makes the absorption bathochromically-shifted together with a much higher molar extinction coefficient, whereas integration of the corannulene unit to the perylene dyes along bay-positions has a much broader absorption. Strong and broad absorption properties, strong electron-accepting ability, and suitable LUMO levels close to that of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) make hybrid corannulene¿perylene dyes promising electron-acceptor materials for organic optoelectronic devices.

DOI 10.1002/asia.201600490
Citations Scopus - 7
2016 Shi X, Liu S, Liu C, Hu Y, Shi S, Fu N, et al., 'Highly Contorted 1,2,5-Thiadiazole-Fused Aromatics for Solution-Processed Field-Effect Transistors: Synthesis and Properties', Chemistry - An Asian Journal, 11 2188-2200 (2016)

© 2016 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim A straightforward strategy has been used to construct 1,2,5-thiadiazole-fused 12-ring p systems through twofold Stille coup... [more]

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim A straightforward strategy has been used to construct 1,2,5-thiadiazole-fused 12-ring p systems through twofold Stille coupling and subsequent cyclodehydrogenation by utilizing the building blocks of naphthodithiophene and 5,6-substituted benzo[b]-2,1,3-thiadidazole. Molecules 1 a and 1 b, which exhibit highly contorted p surfaces, show a butterfly-shaped conformation according to DFT calculations. Within the molecules, a plane-to-plane angle of 44.8° was found. UV/Vis absorption, thermogravimetric analysis, differential scanning calorimetry, and cyclic voltammetry (CV) were used to study their physical properties. Strong intermolecular interactions of the nonplanar molecules were also observed by concentration-dependent1H NMR spectroscopy measurements and thin-film XRD characterization. The low-lying LUMO and high-lying HOMO levels of the molecules are -3.73 and -5.48 eV, respectively, as estimated from CV measurements; this indicates their potential as semiconducting materials for solution-processed organic field-effect transistors (OFETS). A field-effect hole mobility of up to 0.035 cm2V-1s-1, a threshold voltage of 6.98 V, and a current on/off ratio of 8.65×105in air for 1 a have been demonstrated with the top-contact bottom-gate field-effect transistor device structures; this represents an important step toward the solution-processed OFET application of contorted aromatics.

DOI 10.1002/asia.201600675
Citations Scopus - 8
2016 Liu XH, Yue JY, Mo YP, Yao Y, Zeng C, Chen T, et al., 'Surface Host-Guest Supramolecular Assemblies on Porphyrin-Based Covalent Organic Grids', Journal of Physical Chemistry C, 120 15753-15757 (2016)

© 2016 American Chemical Society. The design and construction of stable porous networks featuring tunable cavities for selective guest inclusion remains a great challenge in const... [more]

© 2016 American Chemical Society. The design and construction of stable porous networks featuring tunable cavities for selective guest inclusion remains a great challenge in construction of functional miniature devices. Herein we report on construction and guest inclusion of stable 2D porphyrin-based molecular square grids connected by imine bonds showing crystalline pattern with periodic square cavities. Diperylene diimides molecules can be decorated into the square pores of the porphyrin-based molecular template on HOPG surfaces. The periodicity control over the covalent molecular grid and thus that of guest molecules is demonstrated by changing the building block. The preparation of robust host-guest systems may facilitate the fabrication of molecular miniature devices with designable properties.

DOI 10.1021/acs.jpcc.5b11322
Citations Scopus - 2
2016 Kan X, Xiao C, Li X, Su B, Wu Y, Jiang W, et al., 'A Dewetting-Induced Assembly Strategy for Precisely Patterning Organic Single Crystals in OFETs', ACS Applied Materials and Interfaces, 8 18978-18984 (2016)

© 2016 American Chemical Society. Simple methods for patterning single crystals are critical to fully realize their applications in electronics. However, traditional vapor and sol... [more]

© 2016 American Chemical Society. Simple methods for patterning single crystals are critical to fully realize their applications in electronics. However, traditional vapor and solution methods are deficient in terms of crystals with random spatial and quality distributions. In this work, we report a dewetting-induced assembly strategy for obtaining large-scale and highly oriented organic crystal arrays. We also demonstrate that organic field-effect transistors (OFETs) fabricated from patterned n-alkyl-substituted tetrachloroperylene diimide (R-4ClPDI) single crystals can reach a maximum mobility of 0.65 cm2V-1s-1for C8-4ClPDI in ambient conditions. This technique constitutes a facile method for fabricating OFETs with high performances for large-scale electronics applications.

DOI 10.1021/acsami.6b04163
Citations Scopus - 3
2016 Zhang A, Wang Q, Bovee RAA, Li C, Zhang J, Zhou Y, et al., 'Perfluoroalkyl-substituted conjugated polymers as electron acceptors for all-polymer solar cells: The effect of diiodoperfluoroalkane additives', Journal of Materials Chemistry A, 4 7736-7745 (2016)

© 2016 The Royal Society of Chemistry. A series of six diketopyrrolopyrrole (DPP) based conjugated polymers with a varying content of solubilizing perfluoroalkyl chains were synth... [more]

© 2016 The Royal Society of Chemistry. A series of six diketopyrrolopyrrole (DPP) based conjugated polymers with a varying content of solubilizing perfluoroalkyl chains were synthesized. Based on a systematic investigation of the influence of the solvent on the photovoltaic performance, it is found that 1,6-diiodoperfluorohexane (IC6F12I) is an effective solvent additive to enhance the power conversion efficiency (PCE) of DPP polymers with perfluoroalkyl side chains. The polymers consist of thiazole-flanked DPP units that alternate along the main chain with varying ratios of thiophene (T) and perfluoroalkyl benzodithiophene (FBDT) units. The polymers possess high molecular weights, narrow band gaps and good crystalline properties. The DPP polymers were used as electron acceptors in bulk heterojunction solar cells with another DPP polymer as the electron donor. A solvent mixture of CHCl31-chloronaphthalene (1-CN) is found to provide the best PCE of 2.9% in non-fluorine based DPP polymer solar cells, but yields a low PCE of 0.52% for perfluoroalkyl-containing polymer solar cells. Perfluoroalkyl-containing polymer solar cells fabricated from CHCl3with IC6F12I as the processing additive show a significantly improved PCE of 2.1%. The morphology analysis of the blend films reveals that IC6F12I as an additive improves the micro-phase separation between the polymer donor and acceptor, which results in enhanced charge generation.

DOI 10.1039/c6ta00962j
Citations Scopus - 17
2016 Ren L, Liu C, Wang Z, Zhu X, 'Isomeric indacenedibenzothiophenes: Synthesis, photoelectric properties and ambipolar semiconductivity', Journal of Materials Chemistry C, 4 5202-5206 (2016)

© 2016 The Royal Society of Chemistry. A new strategy via double C-H activation cyclization has been developed for the versatile synthesis of IDBT derivatives with quite different... [more]

© 2016 The Royal Society of Chemistry. A new strategy via double C-H activation cyclization has been developed for the versatile synthesis of IDBT derivatives with quite different photoelectric properties. Single-crystal field-effect transistors based on IDBT-l-TIPSA delivered high and balanced charge carrier mobilities of up to 0.64 cm2V-1s-1for holes and 0.34 cm2V-1s-1for electrons under ambient conditions.

DOI 10.1039/c6tc01808d
Citations Scopus - 7
2016 Wang Z, Li X, Zou Y, Tan J, Fu X, Liu J, et al., 'Tuning charge transport from unipolar (n-type) to ambipolar in bis(naphthalene diimide) derivatives by introducing p-conjugated heterocyclic bridging moieties', Journal of Materials Chemistry C, 4 7230-7240 (2016)

© 2016 The Royal Society of Chemistry. A series of acceptor-donor-acceptor (A-D-A) conjugated molecules based on naphthalene diimide dimers bridged with different p-conjugated het... [more]

© 2016 The Royal Society of Chemistry. A series of acceptor-donor-acceptor (A-D-A) conjugated molecules based on naphthalene diimide dimers bridged with different p-conjugated heterocyclic units (NDI-p-NDI) have been designed and synthesized. By an ingenious design strategy, the LUMO (the lowest unoccupied molecular orbital) of the NDI-based small molecules is well controlled to a relatively constant value of -3.8 to -3.9 eV, whereas their HOMO (the highest occupied molecular orbital) could be tuned over a wide range, from -6.5 eV (compound 1) to -5.5 eV (compound 5), leading to varied band gaps from 2.6 eV to 1.5 eV. Organic field-effect transistor (OFET) characterization of these NDI-p-NDI molecules shows that compounds 1, 2, and 3 have good n-type semiconducting properties in a N2 atmosphere with the maximum electron mobilities up to 0.15 cm2 V-1 s-1, 0.46 cm2 V-1 s-1 and 0.57 cm2 V-1 s-1, respectively. Compounds 4 and 5, due to the high-lying HOMO levels and reduced energy band gaps, have ambipolar semiconducting properties and OFETs based on 5 show the highest electron and hole mobilities up to 1.23 cm2 V-1 s-1 and 0.0074 cm2 V-1 s-1, respectively. Moreover, the performances are enhanced under thermal treatment because of the increased crystallinity as evidenced by X-ray diffraction (XRD) and atomic force microscopy (AFM). The easily tunable electronic energy levels make the NDI-based semiconductors promising n-channel and ambipolar components in organic devices.

DOI 10.1039/c6tc01769j
Citations Scopus - 8
2016 Kan X, Xiao C, Gao H, Wang Z, Wu Y, Su B, et al., 'Top-Pinning Controlled Dewetting for Fabrication of Large-Scaled Polymer Microwires and Applications in OFETs', Advanced Electronic Materials, 2 (2016)
DOI 10.1002/aelm.201600111
Citations Scopus - 2
2016 Zhao G, Gu P, Dong H, Jiang W, Wang Z, Hu W, 'High-Mobility N-Type Organic Field-Effect Transistors of Rylene Compounds Fabricated by a Trace-Spin-Coating Technique', Advanced Electronic Materials, 2 (2016)
DOI 10.1002/aelm.201500430
Citations Scopus - 5
2016 Liu T, Meng D, Cai Y, Sun X, Li Y, Huo L, et al., 'High-Performance Non-Fullerene Organic Solar Cells Based on a Selenium-Containing Polymer Donor and a Twisted Perylene Bisimide Acceptor', Advanced Science, 3 (2016)
DOI 10.1002/advs.201600117
Citations Scopus - 33
2016 Gao G, Zhang X, Meng D, Zhang A, Liu Y, Jiang W, et al., 'Bis(perylene diimide) with DACH bridge as non-fullerene electron acceptor for organic solar cells', RSC Advances, 6 14027-14033 (2016)

© The Royal Society of Chemistry 2016. In this paper, we designed, synthesized, and characterized a set of non-fullerene small molecules based on bis(perylene diimide) with DACH b... [more]

© The Royal Society of Chemistry 2016. In this paper, we designed, synthesized, and characterized a set of non-fullerene small molecules based on bis(perylene diimide) with DACH bridge. Theoretical calculations make clear that the introduction of the DACH bridge into PPDI forms a U-shape framework, with pi-pi interactions between PDIs. We investigate the performances of non-fullerene solar cells comprising racemic and enantiomerically pure DACH-PPDIs as the electron acceptor and PTB7-Th as the electron donor. As a consequence, a power conversion efficiency (PCE) of 4.68% is achieved with inverted device architecture. Furthermore, the device behaviour, morphological feature and charge transport properties were also investigated. It is a potential way to design highly efficient non-fullerene organic solar cell by tuning the structure of PDI to reach highly efficient photovoltaic performances.

DOI 10.1039/c5ra26777c
Citations Scopus - 16
2016 Zeng C, Xiao C, Xin R, Jiang W, Wang Y, Wang Z, 'Influence of alkyl chain branching point on the electron transport properties of di(perylene diimides) thin film transistors', RSC Advances, 6 55946-55952 (2016)

© 2016 The Royal Society of Chemistry. The alkyl chain length and density are fundamental factors affecting solution processability, molecular packing, film microstructure, and ch... [more]

© 2016 The Royal Society of Chemistry. The alkyl chain length and density are fundamental factors affecting solution processability, molecular packing, film microstructure, and charge transport for organic thin film transistors (OTFTs). In this work, four tetra-chlorinated di(perylene diimides) 4CldiPDI-C(1-4) were prepared through moving the alkyl chain branching position away from the di(perylene diimides) backbone. OTFT devices employing 4CldiPDI-C(1-4) as the active layer were fabricated. Correspondingly, the effect of the position of the alkyl chain branching point on the film microstructure and charge transport were studied in detail. The research results demonstrate that the different branching point of side-chains has a negligible effect on the absorption maximum and energy gap. Conversely, the gradual movement in the branching point plays a key role in molecular packing and leads to a clear impact on electron mobility ranging from 0.012 to 0.86 cm2 V-1 s-1. Therefore, 4CldiPDI-C2-based devices offered the highest electron mobility of up to 0.86 cm2 V-1 s-1 and an on/off ratio of 2 × 107, which is among the best performance of diPDI derivatives.

DOI 10.1039/c6ra09781b
Citations Scopus - 5
2016 Fang C, Xiao D, Liu W, Lou X, Zhou J, Wang Z, Liu J, 'Enhanced AOX accumulation and aquatic toxicity during 2,4,6-trichlorophenol degradation in a Co(II)/peroxymonosulfate/Cl
DOI 10.1016/j.chemosphere.2015.11.030
Citations Scopus - 23Web of Science - 23
2016 Jiang B, Wang X, Liu Y, Wang Z, Zheng J, Wu M, 'The roles of polycarboxylates in Cr(VI)/sulfite reaction system: Involvement of reactive oxygen species and intramolecular electron transfer', Journal of Hazardous Materials, 304 457-466 (2016) [C1]
DOI 10.1016/j.jhazmat.2015.11.011
Citations Scopus - 18Web of Science - 14
2016 Zhou J, Xiao JH, Fang CL, Xiao DX, Guo YG, Lou XY, et al., 'Degradation kinetics and mechanisms of chloronitrophenol in UV/PMS system', Zhongguo Huanjing Kexue/China Environmental Science, 36 66-73 (2016)

© 2016, Chinese Society for Environmental Sciences. All right reserved. The efficient removal of 4-chloro-2-nitrophenol (4C2NP) in ultraviolet (UV)/peroxymonosulfate (PMS) oxidati... [more]

© 2016, Chinese Society for Environmental Sciences. All right reserved. The efficient removal of 4-chloro-2-nitrophenol (4C2NP) in ultraviolet (UV)/peroxymonosulfate (PMS) oxidation system was investigated. The effects of pH, PMS dosage and concentrations of 4C2NP, chloride and nitrate ions on the degradation efficiency of 4C2NP were evaluated. No significant differences in 4C2NP degradation rate were observed at pH 2.0~5.0, but a further increase in pH value would inhibit the substrate decomposition. In addition, PMS dosage positively correlated with degradation rates of 4C2NP, while 4C2NP concentration had a negative effect. A typical dual effect of chloride concentrations on the 4C2NP degradation kinetics was observed, whereas the increasing concentrations of nitrate showed an indistinctively inhibitory effect on 4C2NP degradation. Dechlorination and denitration were the dominant degradation pathways during the oxidative degradation of 4C2NP, followed by the formation of chloride and nitrate ions. The released chloride from chloro groups would be involved in re-chlorination through radical reactions. Nitro groups released would be oxidized to stable nitrate, preventing re-nitration. Degradation mechanism of 4C2NP in a UV/PMS system was proposed based on intermediates identified.

Citations Scopus - 3
2016 Liu W, Fang C, Huang Y, Ai L, Yang F, Wang Z, Liu J, 'Is UV/Ce(IV) process a chloride-resistant AOPs for organic pollutants decontamination?', RSC Advances, 6 93558-93563 (2016) [C1]

© The Royal Society of Chemistry 2016. Most of the current advanced oxidation processes (AOPs) are vulnerable to the presence of chloride in saline wastewater treatment because ch... [more]

© The Royal Society of Chemistry 2016. Most of the current advanced oxidation processes (AOPs) are vulnerable to the presence of chloride in saline wastewater treatment because chloride not only affects the degradation kinetics but also probably leads to absorbable organic halogen (AOX) formation. Here we report an UV/Ce(iv) process can efficiently oxidize organic pollutants such as Acid Orange 7, even in the presence of chloride. Fluorescent probe technology suggests hydroxyl radicals were generated in UV/Ce(iv) process, but not in UV/Ce(iv)/Cl-system. In the presence of chloride, Ce(iv)-chloride complex was formed, which can directly oxidize dyes or generate reactive oxygen species by chlorine activation. Although degradation and mineralization rates of dyes were still inhibited to some extents by large amounts of chloride, but negligible AOX was generated. Therefore, UV/Ce(iv) process can be recommended as an alternative AOPs when treating acidic saline wastewater.

DOI 10.1039/c6ra21682j
Citations Scopus - 2Web of Science - 1
2016 Lou X, Xiao D, Fang C, Wang Z, Liu J, Guo Y, Lu S, 'Comparison of UV/hydrogen peroxide and UV/peroxydisulfate processes for the degradation of humic acid in the presence of halide ions', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 23 4778-4785 (2016)
DOI 10.1007/s11356-015-5232-x
Citations Scopus - 14Web of Science - 12
2016 Huang Y, Wang Z, Fang C, Liu W, Lou X, Liu J, 'Importance of reagent addition order in contaminant degradation in an Fe(II)/PMS system', RSC ADVANCES, 6 70271-70276 (2016)
DOI 10.1039/c6ra14081e
Citations Scopus - 7Web of Science - 7
2016 Li X, Wang Z, Zhang B, Rykov AI, Ahmed MA, Wang J, 'Fe
DOI 10.1016/j.apcatb.2015.08.050
Citations Scopus - 96Web of Science - 88
2015 Sun D, Meng D, Cai Y, Fan B, Li Y, Jiang W, et al., 'Non-Fullerene-Acceptor-Based Bulk-Heterojunction Organic Solar Cells with Efficiency over 7%', Journal of the American Chemical Society, 137 11156-11162 (2015)

© 2015 American Chemical Society. A novel perylene bisimide (PBI) dimer-based acceptor material, SdiPBI-S, was developed. Conventional bulk-heterojunction (BHJ) solar cells based ... [more]

© 2015 American Chemical Society. A novel perylene bisimide (PBI) dimer-based acceptor material, SdiPBI-S, was developed. Conventional bulk-heterojunction (BHJ) solar cells based on SdiPBI-S and the wide-band-gap polymer PDBT-T1 show a high power conversion efficiency (PCE) of 7.16% with a high open-circuit voltage of 0.90 V, a high short-circuit current density of 11.98 mA/cm2, and an impressive fill factor of 66.1%. Favorable phase separation and balanced carrier mobilites in the BHJ films account for the high photovoltaic performance. The results demonstrate that fine-tuning of PBI-based materials is a promising way to improve the PCEs of non-fullerene BHJ organic solar cells. (Chemical Equation Presented).

DOI 10.1021/jacs.5b06414
Citations Scopus - 296
2015 Xiao C, Zhao G, Zhang A, Jiang W, Janssen RAJ, Li W, et al., 'High Performance Polymer Nanowire Field-Effect Transistors with Distinct Molecular Orientations', Advanced Materials, 27 4963-4968 (2015)

© 2015 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim. Polymer nanowires based on two diketopyrrolopyrrole conjugated polymers with similar chemical structures are shown to have... [more]

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Polymer nanowires based on two diketopyrrolopyrrole conjugated polymers with similar chemical structures are shown to have distinct "edge-on" and "face-on" configurations in addition to high well-balanced hole and electron mobilities of 5.47 and 5.33 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup> in field-effect transistors.

DOI 10.1002/adma.201502617
Citations Scopus - 32
2015 Liu C, Xu S, Zhu W, Zhu X, Hu W, Li Z, Wang Z, 'Diaceno[a,e]pentalenes: An Excellent Molecular Platform for High-Performance Organic Semiconductors', Chemistry - A European Journal, 21 17016-17022 (2015)

© 2015 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim. Three diaceno[a,e]pentalene analogues with pendant sterically bulky di-tert-butylphenyl groups have been designed and synt... [more]

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Three diaceno[a,e]pentalene analogues with pendant sterically bulky di-tert-butylphenyl groups have been designed and synthesized. With the extension of the conjugated molecular framework, the molecular arrangement is apparently tuned by the balance between the p-extended surface and pendant alkyl or aryl substituents. Theoretical calculations of the morphologies were in good agreement with the experimental results. Ambient-stable field-effect transistors based on dianthraceno[a,e]pentalene (DAP) have been fabricated, which exhibited excellent hole mobilities (up to 6.55 cm2V-1s-1). Thus, this study has shown that diaceno[a,e]pentalenes are stable even with an extraordinarily large p-surface area, and may thus serve as excellent molecular platforms for further exploring high-performance semiconducting materials.

DOI 10.1002/chem.201502184
Citations Scopus - 15
2015 Li C, Liu C, Li Y, Zhu X, Wang Z, 'Facile synthesis of a pyrrole-fused dibenzo[a,e]pentalene and its application as a new extended, ladder-type fused aromatic system', Chemical Communications, 51 693-696 (2015)

© The Royal Society of Chemistry 2015. A novel ladder-type pyrrole-fused dibenzo[a,e]pentalene, in which two benzo[a,e]pentalene units are held coplanar by a nitrogen bridge, is s... [more]

© The Royal Society of Chemistry 2015. A novel ladder-type pyrrole-fused dibenzo[a,e]pentalene, in which two benzo[a,e]pentalene units are held coplanar by a nitrogen bridge, is synthesized via double intermolecular Pd-catalyzed cascade crossover annulations. The introduction of a nitrogen bridge not only has a substantial influence on the optoelectronic properties but also improves the processability and stability. This journal is

DOI 10.1039/c4cc07721k
Citations Scopus - 10
2015 Li X, Zheng Z, Jiang W, Wu W, Wang Z, Tian H, 'New D-A-p-A organic sensitizers for efficient dye-sensitized solar cells', Chemical Communications, 51 3590-3592 (2015)

© The Royal Society of Chemistry 2015. Four novel metal-free D-A-p-A organic sensitizers (ND01-ND04) based on N-annulated perylene (NP) derivatives as efficient electron donors fo... [more]

© The Royal Society of Chemistry 2015. Four novel metal-free D-A-p-A organic sensitizers (ND01-ND04) based on N-annulated perylene (NP) derivatives as efficient electron donors for dye-sensitized solar cells (DSSCs) are designed. Among them, ND02 featuring bulky 4-methoxyphenyl as the additional electron-donating substituents on the NP unit shows a power conversion efficiency as high as 8.30%. This journal is

DOI 10.1039/c4cc08539f
Citations Scopus - 43
2015 Yang L, Zheng Z, Li Y, Wu W, Tian H, Wang Z, 'N-annulated perylene-based metal-free organic sensitizers for dye-sensitized solar cells', Chemical Communications, 51 4842-4845 (2015)

© The Royal Society of Chemistry 2015. A series of novel metal-free organic sensitizers based on N-annulated perylene derivatives have been designed and synthesized, and exhibit b... [more]

© The Royal Society of Chemistry 2015. A series of novel metal-free organic sensitizers based on N-annulated perylene derivatives have been designed and synthesized, and exhibit broad absorption spectra in the visible region. The dye-sensitized solar cells exhibit overall conversion efficiencies ranging from 4.90% to 8.28% under AM 1.5 solar conditions.

DOI 10.1039/c5cc00650c
Citations Scopus - 50
2015 Ye L, Jiang W, Zhao W, Zhang S, Cui Y, Wang Z, Hou J, 'Toward efficient non-fullerene polymer solar cells: Selection of donor polymers', Organic Electronics: physics, materials, applications, 17 295-303 (2015)

© 2014 Elsevier B.V. All rights reserved. Recently, perylene bisimides have been explored and developed as potential candidates for non-fullerene acceptors and power conversion ef... [more]

© 2014 Elsevier B.V. All rights reserved. Recently, perylene bisimides have been explored and developed as potential candidates for non-fullerene acceptors and power conversion efficiencies (PCEs) exceeding 3% were realized in the non-fullerene polymer solar cells (NF-PSCs) featuring perylene bisimides as acceptors. Considering that only a few donor polymers like P3HT and PBDTTT-C-T were utilized in non-fullerene PSCs, screening donor polymers with well-matched energy levels, absorption spectrum as well as hole mobility in NF-PSCs will be the key to promote the current PCEs. Herein, four high performance donor polymers including PBDTTPD, PBDTTT-EFT, PDPP3T, PSBTBT were employed for the optimization of single bond-linked perylene bisimide (SDIPBI)-based NF-PSCs. A clear criterion in selection of donor polymers has been established for the SDIPBI-based NF-PSCs. Suitable energy level differences, finer morphology, and broad absorption ranges could be successively screened for donor polymers. Interestingly, NF-PSCs based on PBDTTPD/SDIPBI delivers a high Voc of 1.04 V and a desirable PCE of 3.4%. Moreover, the SDIPBI-based NF-PSC employing PBDTTT-EFT as donor polymer exhibits a high PCE up to 4.5%. The results implicate that to select donor polymers is a feasible strategy to boost the photovoltaic performance of NF-PSCs further.

DOI 10.1016/j.orgel.2014.12.020
Citations Scopus - 28
2015 Fu Y, Yang Q, Deng Y, Jiang W, Wang Z, Geng Y, Xie Z, 'Suppressed charge recombination in polymer solar cells based on perylene diimide derivative acceptors via solvent vapor annealing', Organic Electronics: physics, materials, applications, 18 24-31 (2015)

© 2015 Elsevier B.V. All rights reserved. A singly-linked perylene bisimide dimer (di-PBI) and a low band gap polymer based on dithienocarbazole and isoindigo moieties (P(IID-DTC)... [more]

© 2015 Elsevier B.V. All rights reserved. A singly-linked perylene bisimide dimer (di-PBI) and a low band gap polymer based on dithienocarbazole and isoindigo moieties (P(IID-DTC)) are selected as electron acceptor and donor respectively to fabricate non-fullerene based polymer solar cells. The combination of di-PBI acceptor and P(IID-DTC) donor provides well overlapped absorption profile with solar light in the visible region. The P(IID-DTC):di-PBI blend morphology and its effect on charge transport and recombination have been investigated in detail. The dominant bimolecular recombination in commonly processed P(IID-DTC):di-PBI blend results in a low power conversion efficiency of merely 1%. We find that CH2Cl2vapor annealing can effectively improve bi-continuous phase separation and boost the electron transport by more than two orders of magnitude due to the detrap of di-PBI molecules from amorphous P(IID-DTC) matrix. More importantly, the dominant bimolecular recombination in the P(IID-DTC):di-PBI blend films is strongly suppressed. Finally, the power conversion efficiency of non-fullerene P(IID-DTC):di-PBI blend solar cell is dramatically improved to 2.95%.

DOI 10.1016/j.orgel.2015.01.008
Citations Scopus - 12
2015 Wu CH, Chueh CC, Xi YY, Zhong HL, Gao GP, Wang ZH, et al., 'Influence of Molecular Geometry of Perylene Diimide Dimers and Polymers on Bulk Heterojunction Morphology Toward High-Performance Nonfullerene Polymer Solar Cells', Advanced Functional Materials, 25 5326-5332 (2015)

© 2015 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim. In this study, we investigate the influence of molecular geometry of the donor polymers and the perylene diimide dimers (d... [more]

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. In this study, we investigate the influence of molecular geometry of the donor polymers and the perylene diimide dimers (di-PDIs) on the bulk heterojunction (BHJ) morphology in the nonfullerene polymer solar cells (PSCs). The results reveal that the pseudo 2D conjugated poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b']dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)] (PTB7-Th) has better miscibility with both bay-linked di-PDI (B-di-PDI) and hydrazine-linked di-PDI (H-di-PDI) compared to its 1D analog, poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7), to facilitate more efficient exciton dissociation in the BHJ films. However, the face-on oriented p-p stacking of PTB7-Th is severely disrupted by the B-di-PDI due to its more flexible structure. On the contrary, the face-on oriented p-p stacking is only slightly disrupted by the H-di-PDI, which has a more rigid structure to provide suitable percolation pathways for charge transport. As a result, a very high power conversion efficiency (PCE) of 6.41% is achieved in the PTB7-Th:H-di-PDI derived device. This study shows that it is critical to pair suitable polymer donor and di-PDI-based acceptor to obtain proper BHJ morphology for achieving high PCE in the nonfullerene PSCs.

DOI 10.1002/adfm.201501971
Citations Scopus - 70
2015 Zhang X, Xiao C, Zhang A, Yang F, Dong H, Wang Z, et al., 'Pyridine-bridged diketopyrrolopyrrole conjugated polymers for field-effect transistors and polymer solar cells', Polymer Chemistry, 6 4775-4783 (2015)

© The Royal Society of Chemistry 2015. Five wide or medium band gap diketopyrrolopyrrole (DPP)-based conjugated polymers with pyridine as bridges were developed for organic field-... [more]

© The Royal Society of Chemistry 2015. Five wide or medium band gap diketopyrrolopyrrole (DPP)-based conjugated polymers with pyridine as bridges were developed for organic field-effect transistors (OFETs) and polymer solar cells (PSCs). By introducing copolymerized aromatic building blocks from strong electron-donating units to electron-deficient units into the conjugated backbone, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of the DPP polymers were tailored to the low-lying position. Therefore, the polarity of charge transport in OFETs can be switched from p-type to n-type. The DPP polymer with a low-lying LUMO of -3.80 eV provides a hole-only mobility of 2.95 × 10-2 cm2 V-1 s-1, while an electron-only mobility of 1.24 × 10-3 cm2 V-1 s-1 is found in the DPP polymer with a LUMO of -4.22 eV. Further investigation of photovoltaic cells based on these DPP polymers shows a modest power conversion efficiency (PCE) of around 2%. Our results demonstrate that wide band gap pyridine-bridged DPP polymers have potential application in OFETs and OSCs by adjusting their energy level with alternated units on the conjugated backbone.

DOI 10.1039/c5py00538h
Citations Scopus - 18
2015 Ye L, Sun K, Jiang W, Zhang S, Zhao W, Yao H, et al., 'Enhanced efficiency in fullerene-free polymer solar cell by incorporating fine-designed donor and acceptor materials', ACS Applied Materials and Interfaces, 7 9274-9280 (2015)

© 2015 American Chemical Society. Among the diverse nonfullerene acceptors, perylene bisimides (PBIs) have been attracting much attention due to their excellent electron mobility ... [more]

© 2015 American Chemical Society. Among the diverse nonfullerene acceptors, perylene bisimides (PBIs) have been attracting much attention due to their excellent electron mobility and tunable molecular and electronic properties by simply engineering the bay and head linkages. Herein, guided by two efficient small molecular acceptors, we designed, synthesized, and characterized a new nonfullerene small molecule PPDI with fine-tailored alkyl chains. Notably, a certificated PCE of 5.40% is realized in a simple structured fullerene-free polymer solar cell comprising PPDI as the electron acceptor and a fine-tailored 2D-conjugated polymer PBDT-TS1 as the electron donor. Moreover, the device behavior, morphological feature, and origin of high efficiency in PBDT-TS1/PPDI-based fullerene-free PSC were investigated. The synchronous selection and design of donor and acceptor materials reported here offer a feasible strategy for realizing highly efficient fullerene-free organic photovoltaics.

DOI 10.1021/acsami.5b02012
Citations Scopus - 76
2015 He B, Ren Z, Qi C, Yan S, Wang Z, 'Synthesis of nitrogen-doped monolayer graphene with high transparent and n-type electrical properties', Journal of Materials Chemistry C, 3 6172-6177 (2015)

© 2015 The Royal Society of Chemistry. A one-step synthesis of a large-area and highly nitrogen-doped graphene (NG) membrane with few defects derived from poly 4-vinyl pyridine (P... [more]

© 2015 The Royal Society of Chemistry. A one-step synthesis of a large-area and highly nitrogen-doped graphene (NG) membrane with few defects derived from poly 4-vinyl pyridine (P4VP) has been reported. The synthesis temperature has been optimized by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). With this approach, a large-area of more than 80% single-layer NG membrane with a nitrogen content of 6.37% can be obtained. Scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman mapping-mode, optical microscopy (OM) and transmission electron microscopy (TEM) analyses reveal that the resultant NG is a flat, continuous, uniform and monolayered graphene membrane with a large area and a well-ordered crystalline structure. The electrical measurement confirms the typical n-type field-effect transistors (FETs) for NG both in air and vacuum, and the electron mobility can reach as high as 365 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup>, much higher than those of NGs previously reported. In addition, the transmittance and sheet resistance of NG correlates well with a monolayered structure and semiconducting properties, which also makes it a candidate of transparent electrode for various optoelectronic devices.

DOI 10.1039/c5tc01046b
Citations Scopus - 11
2015 Zhang A, Xiao C, Meng D, Wang Q, Zhang X, Hu W, et al., 'Conjugated polymers with deep LUMO levels for field-effect transistors and polymer-polymer solar cells', Journal of Materials Chemistry C, 3 8255-8261 (2015)

© The Royal Society of Chemistry 2015. Three thiazole-bridged DPP polymers with deep lowest unoccupied molecular orbital (LUMO) levels were designed for field-effect transistors (... [more]

© The Royal Society of Chemistry 2015. Three thiazole-bridged DPP polymers with deep lowest unoccupied molecular orbital (LUMO) levels were designed for field-effect transistors (FETs) and polymer-polymer solar cells. By introducing thiazole-thiazole coupled segments, perfluoroalkyl side chains or strong electron-deficient naphthalenediimide units into the conjugated backbone the three thiazole-bridged DPP polymers have LUMO levels of -4.0 to -4.4 eV. The three DPP polymers exhibit optical absorption in the near-infrared region, crystallinity and an electron mobility of around 0.01 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup> in bottom contact FETs. The polymers were applied as electron acceptors in polymer-polymer solar cells to provide PCEs of around 0.4%. The low PCEs are mainly due to low short-circuit currents (J<inf>sc</inf>) and attributed to large phase separation. Our results demonstrate several efficient strategies to lower the energy levels of conjugated polymers in order to be used as universal acceptors for photovoltaic cells.

DOI 10.1039/c5tc01313e
Citations Scopus - 11
2015 Jiang B, Liu Y, Zheng J, Tan M, Wang Z, Wu M, 'Synergetic Transformations of Multiple Pollutants Driven by Cr(VI)-Sulfite Reactions', Environmental Science and Technology, 49 12363-12371 (2015) [C1]

© 2015 American Chemical Society. Reduction of Cr(VI) is often deemed necessary to detoxify chromium contaminants; however, few investigations utilized this reaction for the purpo... [more]

© 2015 American Chemical Society. Reduction of Cr(VI) is often deemed necessary to detoxify chromium contaminants; however, few investigations utilized this reaction for the purpose of treating other industrial wastewaters. Here a widely used Cr(VI)-sulfite reaction system was upgraded to simultaneously transform multiple pollutants, namely, the reduction of Cr(VI) and oxidation of sulfite and other organic/inorganic pollutants in an acidic solution. As(III) was selected as a probe pollutant to examine the oxidation capacity of a Cr(VI)-sulfite system. Both¿OH and SO4¿-were considered as the primary oxidants for As(III) oxidation, based on the results of electron spin resonance, fluorescence spectroscopy, and specific radicals quenching. As(III)-scavenging, oxidative radicals greatly accelerated Cr(VI) reduction and simultaneously consumed less sulfite. In comparison with a Cr(VI)-H2O2system with 50 µM Cr(VI), Cr(VI), the sulfite system had excellent performance for both As(III) oxidation and Cr(VI) reduction at pH 3.5. Moreover, in this escalated process, less sulfite was required to reduce Cr(VI) than the traditional Cr(VI) reduction by sulfite process. This effectively improves the environmental compatibility of this Cr(VI) detoxification process, alleviating the potential for SO2release and sulfate ion production in water. Generally, this study provides an excellent example of a "waste control by waste" strategy for the detoxification of multiple industrial pollutants.

DOI 10.1021/acs.est.5b03275
Citations Scopus - 42Web of Science - 38
2015 Wang Z, Xiao D, Bush RT, Liu J, 'Coprecipitated arsenate inhibits thermal transformation of 2-line ferrihydrite: Implications for long-term stability of ferrihydrite', Chemosphere, 122 88-93 (2015) [C1]

© 2014 Elsevier Ltd. 2-line ferrihydrite, a ubiquitous iron oxy-hydroxide found in natural and engineered systems, is an efficient sink for the toxic metalloids such as arsenic. W... [more]

© 2014 Elsevier Ltd. 2-line ferrihydrite, a ubiquitous iron oxy-hydroxide found in natural and engineered systems, is an efficient sink for the toxic metalloids such as arsenic. While much is known of the excellent capacity of ferrihydrite to coprecipitate arsenate, there is little information concerning the long-term stability of arsenate-accumulated ferrihydrite. By thermal treatment methodology, the expedited transformation of ferrihydrite in the presence of coprecipitated arsenate was studied at varying As/Fe ratios (0-0.5) and different heating temperature (40, 300, 450, 600. °C). Pure and transformed minerals were characterized by thermogravimetry (TG), X-ray diffraction (XRD), Electron Spin Resonance (ESR), Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX) and Fourier Transform Infrared Spectroscopy (FTIR). Arsenate was found to retard the thermal transformation of ferrihydrite. The extents of ferrihydrite transformation to hematite decreased with increasing As/Fe ratios, but increased at a higher heating temperature. It is predicted that the coprecipitated arsenate can stabilize the amorphous iron oxides against the transformation to more crystalline solids. Arsenate concentration appears to play an important role in this predicted long-term stability.

DOI 10.1016/j.chemosphere.2014.11.017
Citations Scopus - 12Web of Science - 9
Co-authors Richard Bush
2015 Zhou J, Xiao J, Xiao D, Guo Y, Fang C, Lou X, et al., 'Transformations of chloro and nitro groups during the peroxymonosulfate-based oxidation of 4-chloro-2-nitrophenol', Chemosphere, 134 446-451 (2015) [C1]

© 2015 Elsevier Ltd. Dechlorination and denitration are known to occur during the oxidative degradation of chloronitroaromatic compounds, but the possibility of re-chlorination an... [more]

© 2015 Elsevier Ltd. Dechlorination and denitration are known to occur during the oxidative degradation of chloronitroaromatic compounds, but the possibility of re-chlorination and re-nitration of chloro and nitro groups is not assessed despite of its importance in evaluating the applicability of advanced oxidation processes (AOPs). In this study, transformation of chloro and nitro groups in degradation of 4-chloro-2-nitrophenol (4C2NP) by sulfate radical generated via Co-mediated peroxymonosulfate activation was investigated. Both chloride and nitrate ions were found as the main inorganic products of chloro and nitro groups in 4C2NP, but their levels were much lower than that of degraded parent 4C2NP. A typical dual effect of chloride on the 4C2NP degradation kinetics was observed, whereas no measurable influence was found for addition of low level nitrate. Re-chlorination took place, but re-nitration was not verified because several polychlorophenols but none of polynitrophenols were detected. The specific degradation mechanism involved in the transformation of nitro group and chloro group was proposed.

DOI 10.1016/j.chemosphere.2015.05.027
Citations Scopus - 34Web of Science - 28
2015 Li J, Luo G, Gao J, Yuan S, Du J, Wang Z, 'Quantitative evaluation of potential ecological risk of heavy metals in sewage sludge from three wastewater treatment plants in the main urban area of Wuxi, China', Chemistry and Ecology, 31 235-251 (2015)

© 2014, © 2014 Taylor &amp; Francis. In this study, the potential ecological risks and eco-toxicity of heavy metals (Cu, Pb, Zn, Ni, Cd, Cr, As and Hg) in sewage sludge were qua... [more]

© 2014, © 2014 Taylor & Francis. In this study, the potential ecological risks and eco-toxicity of heavy metals (Cu, Pb, Zn, Ni, Cd, Cr, As and Hg) in sewage sludge were quantitatively evaluated. Sewage sludge samples were collected from three wastewater treatment plants in Wuxi city during five years from 2009 to 2013. The levels of the eight metals temporally varied. The contents of Zn and Cu in the tested sewage sludge were the highest, followed by Cr, Ni, Pb and As, and the contents of Cd and Hg were the least. The Community Bureau of Reference (BCR) sequential extraction results showed that Zn, Ni and Cd had the highest mobilisation potential, while Cu, Pb, Cr and Hg were not stabilised and would release to the environment under oxidising conditions. The removal efficiency of Cu and Cr was higher than 70%, while that of As, Cd and Hg was less than other heavy metals. The overall potential ecological risk index (RI) of heavy metals in sewage sludge was 1376.34, revealing very high risk. However, the environmental risk values based on the index of geo-accumulation (I<inf>geo</inf>) and risk assessment code (RAC) were both low. Cd contamination is the major concern while the treated sewage sludge is used for agricultural purposes.

DOI 10.1080/02757540.2014.961439
Citations Scopus - 8Web of Science - 12
2015 Jiang B, Guo J, Wang Z, Zheng X, Zheng J, Wu W, et al., 'A green approach towards simultaneous remediations of chromium(VI) and arsenic(III) in aqueous solution', Chemical Engineering Journal, 262 1144-1151 (2015) [C1]

© 2014 Elsevier B.V. In this study, the applicability of glow discharge plasma for simultaneous redox transformations of Cr(VI) and As(III) was evaluated in aqueous solution. The ... [more]

© 2014 Elsevier B.V. In this study, the applicability of glow discharge plasma for simultaneous redox transformations of Cr(VI) and As(III) was evaluated in aqueous solution. The results showed that there was a beneficially synergistic effect between Cr(VI) reduction and As(III) oxidation. The presence of Cr(VI) can significantly enhance As(III) oxidation, whereas a slight increase for Cr(VI) reduction mediated by As(III) was observed. The added ethanol or dicarboxylic acids can increase the Cr(VI) reduction with different mechanisms, but significantly retard As(III) oxidation. The conversions of both As(III) and Cr(VI) can also be effectively increased from 96% to 100% and 53% to 77%, respectively, by increasing the voltage input from 530 to 600V. Cr(VI) reduction proceeded more rapidly, approximately 96% at pH 2.0, while As(III) oxidation was depressed under acidic conditions, only 70% at pH 2.0. And the optimal pH value for As(V) formation facilitated by Cr(VI) is 7.0. H2O2generated in-situ in glow discharge plasma can reduce Cr(VI) and produce highly oxidizingOH that was responsible for As(III) oxidation. Reaction between As(III) andOH in turn partially avoided the re-oxidation of Cr(III) byOH to Cr(VI), thus facilitating the net conversion of Cr(VI). Our study demonstrated the feasibility of GDP for the coconversion of As(III) and Cr(VI), holding a great promise for real-world wastewater remediation.

DOI 10.1016/j.cej.2014.10.064
Citations Scopus - 23Web of Science - 15
2015 Xiao D, Lou X, Liu R, Guo Y, Zhou J, Fang C, et al., 'Fe-catalyzed photoreduction of Cr(VI) with dicarboxylic acid (C<inf>2</inf>¿C<inf>5</inf>): divergent reaction pathways', Desalination and Water Treatment, 56 1020-1028 (2015)

© 2014 Balaban Desalination Publications. All rights reserved. Reduction of carcinogenic hexavalent chromium (Cr(VI)) by ferrous iron (Fe(II)) to essentially nontoxic trivalent ch... [more]

© 2014 Balaban Desalination Publications. All rights reserved. Reduction of carcinogenic hexavalent chromium (Cr(VI)) by ferrous iron (Fe(II)) to essentially nontoxic trivalent chromium (Cr(III)) is a simple and effective method for Cr(VI) decontamination. In this study, the photoreduction efficacy of Cr(VI) in acidic Fe(III)/Fe(II) solutions was examined in the presence of dicarboxylic acids (DCA) (i.e. oxalic acid (Oxal), malonic acid (Mal), succinic acid (Suc), and glutaric acid (Glu)). Rates of Cr(VI) reduction under UV irradiation depend on the photochemistry of Fe(III)/Fe(II) complexes with DCA, following the order of Oxal > Suc ¿ Glu > Mal. Fe(III)-oxalato complexes are favorable for transforming Cr(VI) due to the formation of relative abundance of Fe(II) and reductive radicals such as (Formula presented.) , (Formula presented.) after photoreaction, whereas Fe(III)-Mal complexes upon UV irradiation generate the lowest amount of Fe(II) among all the Fe-DCA complexes, and thus have poor capacity for Cr(VI) reduction. The effects of Suc and Glu on the Cr(VI) reduction are insignificant since the Fe(III)-OH complexes are still the main Fe(III) species due to their weak chelating abilities with Fe(III). This work has important implications for selecting the favorable ligands of Fe(III) for light-induced Cr(VI) transformation and designing the methods for treating wastewater with low-molecular-weight acids and Cr(VI).

DOI 10.1080/19443994.2014.941309
Citations Scopus - 3Web of Science - 2
2015 Ramjaun SN, Wang Z, Yuan R, Liu J, 'Can electrochemical oxidation techniques really decontaminate saline dyes wastewater?', Journal of Environmental Chemical Engineering, 3 1648-1653 (2015)

© 2015 Elsevier Ltd. All rights reserved. Formation of toxic chlorinated organic byproducts is of great concern when selecting electrochemical oxidation (EO) as decontamination te... [more]

© 2015 Elsevier Ltd. All rights reserved. Formation of toxic chlorinated organic byproducts is of great concern when selecting electrochemical oxidation (EO) as decontamination technology for saline dye wastewater, but still not verified. To test the applicability of EO, methyl orange (MO) was used as a model dye for anodic contact glow discharge electrolysis (CGDE) and conventional electrolysis (CE) in the presence of chloride. The degradation kinetics and organic intermediates were analyzed. In the presence of chloride, the rates of dye degradation were significantly increased as CGDE and CE were applied. CE resulted in higher mineralization efficiency than CGDE which needs much energy input. Several refractory chlorinated aromatic and even aliphatic compounds were identified during MO degradation, as well as the other anthraquinone dye, alizarin red S (AR). Therefore, the issues of toxic chlorinated byproducts and energy cost should be preferentially evaluated prior to the selection of EO technologies.

DOI 10.1016/j.jece.2015.06.006
Citations Scopus - 5
2014 Shao Q, Niu Z, Hirtz M, Jiang L, Liu Y, Wang Z, Chen X, 'High-performance and tailorable pressure sensor based on ultrathin conductive polymer film', Small, 10 1466-1472 (2014)

A highly sensitive and tailorable pressure sensor is designed based on the variation of contact resistance between an Au covered micropillar array and a conductive polymer film. T... [more]

A highly sensitive and tailorable pressure sensor is designed based on the variation of contact resistance between an Au covered micropillar array and a conductive polymer film. The sensitivity of such pressure sensors can be tuned from 0.03 kPa-1 to 17 kPa-1 at pressures less than 1 kPa, and a limit of detection of 2 Pa has been demonstrated. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/smll.201303601
Citations Scopus - 59
2014 Jiang W, Li Y, Wang Z, 'Tailor-made Rylene arrays for high performance n-channel semiconductors', Accounts of Chemical Research, 47 3135-3147 (2014)

© 2014 American Chemical Society. ConspectusRylene dyes, made up of naphthalene units linked in peri-positions, are emerging as promising key building blocks to create p-functiona... [more]

© 2014 American Chemical Society. ConspectusRylene dyes, made up of naphthalene units linked in peri-positions, are emerging as promising key building blocks to create p-functional materials. Chemists have found uses for these ribbonlike structures in a wide range of applications of optoelectronic devices. Because their structure combines two sets of six-membered electron-withdrawing dicarboxylic imide rings, rylene diimides exhibit enhanced solubility, excellent chemical and thermal stabilities, high electron affinities, and remarkable electron-transporting properties. Among them, perylene diimide (PDI) and naphthalene diimide (NDI) derivatives are important representatives improving the performance of electron-transporting technologies, relative to their p-channel counterparts.Pioneering works by Müllen and Langhals have inspired chemists to extend the p-conjugation along the peri-positions of rylene diimides, which generally results in impressive bathochromic shifts and a nearly linear increase in the extinction coefficient. In addition, in the past years, researchers have focused on p-expansion of NDI or PDI systems through bay-functionalization with carbocyclic and heterocyclic rings annulated onto the skeleton. However, chemists have rarely investigated lateral expansion via both bay- and nonbay-functionalization to construct homologous series of rylene arrays with different electronic delocalization and fine-tuned flexible linkage. This is probably due to the lack of effective procedures for the (multi) carbon-carbon formation and annulation of electron-deficient rylene imide units.In this Account, we discuss our recent progress in the design and synthesis of laterally expanded rylene dyes based on homocoupling and cross-coupling reactions of core-functionalized PDIs and NDIs to achieve novel high performance n-channel organic semiconducting materials. These new achievements offer us opportunities to learn fundamental issues about how chemical and physical properties alter with incremental changes in structure. We highlight synthetic methodology of transition-metal mediated coupling reactions (and/or C-H transformation) for singly linked, doubly linked, and fully conjugated triply linked oligoPDIs, and further for the construction of hybrid rylene arrays via bay- and/or nonbay-functionalization. In addition, we summarize the informative correlations between the molecular structures and their optoelectronic properties, especially the modulation of progressively red-shifted absorption maxima and positive shifts in the redox potentials. This decreases the energy gaps and increases the electron-accepting abilities through expansion of p-system, which has direct impacts on the compounds" potential applications in optoelectronic devices. Finally, we introduce the promising applications of these laterally expanded rylene dyes as exceptional high performance n-channel semiconductors in organic field-effect transistors (OFETs) and competitive candidates for non-fullerene acceptors in high efficient organic photovoltaic devices (OPVs).

DOI 10.1021/ar500240e
Citations Scopus - 130
2014 Yang L, Xiao C, Jiang W, Wang Z, 'Conjugated donor-acceptor copolymers from dicyanated naphthalene diimide', Tetrahedron, 70 6265-6270 (2014)

© 2014 Elsevier Ltd. All rights reserved. Abstract A series of donor-acceptor (D-A) alternating copolymers including P(2CNNDI-T), P(2CNNDI-TT), P(2CNNDI-BT), and P(2CNNDI-BDT) bas... [more]

© 2014 Elsevier Ltd. All rights reserved. Abstract A series of donor-acceptor (D-A) alternating copolymers including P(2CNNDI-T), P(2CNNDI-TT), P(2CNNDI-BT), and P(2CNNDI-BDT) based on dicyanated naphthalene diimide (2CN-NDI) in backbones were presented and characterized in this contribution. Their structures were unambiguously identified by NMR spectra. Optical and electrochemical measurements revealed that their LUMO energy levels are substantially lowered at about -4.4 eV by the substitution of electron-deficient cyano groups on the backbone of as-synthesized polymers. And the HOMO levels varied from -6.15 eV to -5.70 eV as a reflection of electron-donating ability of combined thiophene derivatives. The moderate electron-transporting characteristics under ambient conditions based on these dicyanated polymers indicated their promising applications as air-stable electron transporting semiconductors in future electronics.

DOI 10.1016/j.tet.2014.04.002
Citations Scopus - 5
2014 Sun Y, Fu W, Li Z, Wang Z, 'Tailorable aqueous dispersion of single-walled carbon nanotubes using tetrachloroperylene-based bolaamphiphiles via noncovalent modification', Langmuir, 30 8615-8620 (2014)

The enhanced dispersing capability of these bolaamphiphiles can be attributed to the large aromatic perylene core. The aqueous dispersion efficiency of single-walled carbon nanotu... [more]

The enhanced dispersing capability of these bolaamphiphiles can be attributed to the large aromatic perylene core. The aqueous dispersion efficiency of single-walled carbon nanotubes (SWCNTs) is investigated by UV-vis absorption, fluorescence emission and Raman spectra, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. It is found that the tetrachloroperylene backbone moieties could interact with SWCNT via synergistic p-p and hydrophobic interactions, and the dispersing properties are closely related to the hydrophilic part of bolaamphiles. This study not only demonstrates tetrachloroperylene derivatives are able to stabilize SWCNTs, but also provides the possibility to understand the structure-property relationship between SWCNTs and tetrachloroperylene-based surfactants. © 2014 American Chemical Society.

DOI 10.1021/la502222d
Citations Scopus - 10
2014 Sun K, Xiao C, Liu C, Fu W, Wang Z, Li Z, 'Thermally sensitive self-assembly of glucose-functionalized tetrachloro-perylene bisimides: From twisted ribbons to microplates', Langmuir, 30 11040-11045 (2014)

© 2014 American Chemical Society. Chiral supramolecular structures are becoming increasingly attractive for their specific molecular arrangements, exceptional properties, and prom... [more]

© 2014 American Chemical Society. Chiral supramolecular structures are becoming increasingly attractive for their specific molecular arrangements, exceptional properties, and promising applications in chiral sensing and separation. However, constructing responsive chiral supramolecular structures remains a great challenge. Here, glucosefunctionalized tetrachloro-perylene bisimides (GTPBIs) with thermally sensitive self-assembly behaviors are designed and synthesized. In a methanol/water mixture, GTPBIs self-assembled into twisted ribbons and microplates at 4 and 25 °C, respectively. Furthermore, the ribbon structure was metastable and could transform into microplates when the temperature was increased from 4 to 25 °C. Transmission electron microscopy (TEM) was used to track the evolution of morphology and study the assembly mechanisms of correponding nanostructures at different time intervals. The supramolecular structures were characterized with various techniques, including circular dichroism, TEM, scanning electron microscopy, atomic force microscopy, ultraviolet-visible absorption, and fluorescence spectra. This study provides insight into controlling molecular parameters and assembly conditions to construct chiral supramolecular structures.

DOI 10.1021/la502532g
Citations Scopus - 14
2014 Zang Y, Li CZ, Chueh CC, Williams ST, Jiang W, Wang ZH, et al., 'Integrated molecular, interfacial, and device engineering towards high-performance non-fullerene based organic solar cells', Advanced Materials, 26 5708-5714 (2014)

High-performance non-fullerene OSCs with PCEs of up to ca. 6.0% are demonstrated based on PBDTT-F-TT polymer and a molecular di-PBI acceptor through comprehensive molecular, inter... [more]

High-performance non-fullerene OSCs with PCEs of up to ca. 6.0% are demonstrated based on PBDTT-F-TT polymer and a molecular di-PBI acceptor through comprehensive molecular, interfacial, and device engineering. Impressive PCEs can also be retained in devices with relatively thick BHJ layer and processed through non-halogenated solvents, indicating these high-performance non-fullerene OSCs are promising for large-area printing applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/adma.201401992
Citations Scopus - 295
2014 Yue W, Jiang W, Böckmann M, Doltsinis NL, Wang Z, 'Regioselective functionalization of core-persubstituted perylene diimides', Chemistry - A European Journal, 20 5209-5213 (2014)

Regioselective functionalization of core per-substituted perylene diimides has been achieved efficiently based on a new versatile building block, named tetrabromotetrachloro-peryl... [more]

Regioselective functionalization of core per-substituted perylene diimides has been achieved efficiently based on a new versatile building block, named tetrabromotetrachloro-perylene-3,4:9,10-tetracarboxylic acid dianhydride (Br4Cl4-PTCDA), which affords a series of novel chromophores with impressive optoelectronic properties. Direct palladium-catalyzed fourfold intramolecular ring fusion affords successfully unique propeller-shaped biscarbazole[2,3-b]carbazole diimides with six annulated rings. Organic electronics: A series of novel chromophores were afforded by regioselective functionalization of core per-substituted perylene diimides (PDIs) (see scheme). Furthermore, new carbazole diimide derivatives with an extended p-conjugated system were synthesized by direct palladium-catalyzed intramolecular ring fusion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/chem.201400397
Citations Scopus - 17
2014 Lu X, Sun J, Liu Y, Shao J, Ma L, Zhang S, et al., 'Decorating tetrathiafulvalene (TTF) with fluorinated phenyls through sulfur bridges: Facile synthesis, properties, and aggregation through fluorine interactions', Chemistry - A European Journal, 20 9650-9656 (2014)

Tetrathiafulvalene derivatives (TTF1-TTF9) bearing fluorinated phenyl groups attached through the sulfur bridges have been synthesized by employing a copper-mediated C-S coupling ... [more]

Tetrathiafulvalene derivatives (TTF1-TTF9) bearing fluorinated phenyl groups attached through the sulfur bridges have been synthesized by employing a copper-mediated C-S coupling reaction of C6H5-xFxI (x=1, 2, 5) and a zinc-thiolate complex, (TBA)2[Zn(DMIT)2] (TBA=tetrabutyl ammonium, DMIT=1,3-dithiole-2-thione-4,5-dithiolate), as the key step. Particularly, the selective synthesis of C6F5-substituted (TTF8) and C6F4-fused (TTF9) TTFs from C6F5I is disclosed. The physicochemical properties and crystal structures of these TTFs are fully investigated by UV/Vis absorption spectra, cyclic voltammetry, molecular orbital calculation, and single-crystal X-ray diffraction. The exchange of hydrogen versus fluorine on the peripheral phenyl groups show a notable influence on both the electronic and crystallographic natures of the resulting TTFs: 1) lowering both the HOMO and the LUMO energy levels, 2) modulating the electrochemical properties by regioselective and/or the degree of fluorination, 3) enhancing the driving forces of stacking by multiple fluorine interactions (FS, C-Fp/pF, C-FF-C, and C-FH). This work indicates that the decoration with fluorinated phenyls holds promise to produce functional TTFs with novel electronic and aggregation features. Interacting with fluorine: A library of TTF derivatives bearing fluorinated phenyls attached through sulfur bridges was created (see figure). The electronic and aggregation natures of the TTFs are substantially influenced by the peripheral fluorinated phenyls, by lowering the HOMO and LUMO energy levels, modulating the electrochemical activities, and reinforcing the aggregation driving forces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/chem.201402327
Citations Scopus - 9
2014 Jiang W, Ye L, Li X, Xiao C, Tan F, Zhao W, et al., 'Bay-linked perylene bisimides as promising non-fullerene acceptors for organic solar cells', Chemical Communications, 50 1024-1026 (2014)

A series of bay-linked perylene bisimides as non-fullerene acceptors for organic solar cells are designed. The best power conversion efficiency up to 3.63% based on s-diPBI (1b) i... [more]

A series of bay-linked perylene bisimides as non-fullerene acceptors for organic solar cells are designed. The best power conversion efficiency up to 3.63% based on s-diPBI (1b) is demonstrated by fine-tuning optoelectronic properties resulting from different degrees of twisting and flexibility by bay-linkages. © 2014 The Royal Society of Chemistry.

DOI 10.1039/c3cc47204c
Citations Scopus - 204
2014 Liu C, Xiao C, Li Y, Hu W, Li Z, Wang Z, 'High performance, air stable n-type single crystal transistors based on core-tetrachlorinated perylene diimides', Chemical Communications, 50 12462-12464 (2014)

© the Partner Organisations 2014. Organic single crystal transistors based on two kinds of core-tetrachlorinated perylene diimides (4ClPDIs) are fabricated. Compared with alkyl su... [more]

© the Partner Organisations 2014. Organic single crystal transistors based on two kinds of core-tetrachlorinated perylene diimides (4ClPDIs) are fabricated. Compared with alkyl substituted 4ClPDI, the transistors based on fluoroalkyl substituted 4ClPDI exhibit an air-stable electron mobility of up to 1.43 cm2 V-1 s-1 and high photocurrent with an on/off ratio of 1000, which are associated with its close packing arrangement.

DOI 10.1039/c4cc05896h
Citations Scopus - 21
2014 Gao J, Xiao C, Jiang W, Wang Z, 'Cyano-substituted perylene diimides with linearly correlated LUMO levels', Organic Letters, 16 394-397 (2014)

A series of nonbay region cyano-substituted tetrachloroperylene diimides with tunable LUMO energy levels from -4.21 to -4.64 eV were developed. The excellent linear correlation be... [more]

A series of nonbay region cyano-substituted tetrachloroperylene diimides with tunable LUMO energy levels from -4.21 to -4.64 eV were developed. The excellent linear correlation between LUMO energy levels and the number of cyano groups indicated that the LUMO energy levels could be lowered effectively and predictably by incorporating cyano groups. © 2013 American Chemical Society.

DOI 10.1021/ol403250r
Citations Scopus - 31
2014 He B, Shen Y, Ren Z, Xiao C, Jiang W, Liu L, et al., 'Defect-controlled synthesis of graphene based nano-size electronic devices using in situ thermal treatment', Organic Electronics: physics, materials, applications, 15 685-691 (2014)

Defect-controllable reduction approach of graphene is demonstrated. By in situ thermal reduction from graphene oxide on silicon wafer (300 nm SiO 2), large size (~15 µm) of single... [more]

Defect-controllable reduction approach of graphene is demonstrated. By in situ thermal reduction from graphene oxide on silicon wafer (300 nm SiO 2), large size (~15 µm) of single and few-layer graphene with highly improved electrical properties has been prepared. The effects of increasing annealing temperature on reducing the defect, restoring the lattice and enhancing the field-effect performance of graphene are proved. The characteristics of the sample were analyzed using optical microscope (OM), atomic force microscope (AFM), X-ray photoelectron spectra (XPS), Raman laser, semiconductor parameter analyzer and a micromanipulator. The devices based on the obtained few-layer graphene exhibit relatively high p-type transistor characteristics (6.2 cm2/V s) in the atmospheric environment. © 2014 Elsevier B.V. All rights reserved.

DOI 10.1016/j.orgel.2013.12.029
Citations Scopus - 3
2014 Zhang H, Franke JH, Zhong D, Li Y, Timmer A, Arado OD, et al., 'Surface supported gold-organic hybrids: On-surface synthesis and surface directed orientation', Small, 10 1361-1368 (2014)

The surface-assisted synthesis of gold-organic hybrids on Au (111) and Au (100) surfaces is repotred by thermally initiated dehalogenation of chloro-substituted perylene-3,4,9,10-... [more]

The surface-assisted synthesis of gold-organic hybrids on Au (111) and Au (100) surfaces is repotred by thermally initiated dehalogenation of chloro-substituted perylene-3,4,9,10-tetracarboxylic acid bisimides (PBIs). Structures and surface-directed alignment of the Au-PBI chains are investigated by scanning tunnelling microscopy in ultra high vacuum conditions. Using dichloro-PBI as a model system, the mechanism for the formation of Au-PBI dimer is revealed with scanning tunnelling microscopy studies and density functional theory calculations. A PBI radical generated from the homolytic C-Cl bond dissociation can covalently bind a surface gold atom and partially pull it out of the surface to form stable PBI-Au hybrid species, which also gives rise to the surface-directed alignment of the Au-PBI chains on reconstructed Au (100) surfaces. Stable gold-organic hybrids can be prepared on single crystal gold surfaces via a surface assisted coupling reaction between chloro-substituted perylene-3,4,9,10-tetracarboxylic acid bisimides (PBIs) and surface gold atoms in an ultrahigh vacuum environment. Participation of surface gold atoms in the coupling reaction leads to the oriented alignment of the Au-PBI chains on reconstructed Au (100) surfaces. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/smll.201303011
Citations Scopus - 36
2014 Ye L, Jiang W, Zhao W, Zhang S, Qian D, Wang Z, Hou J, 'Selecting a donor polymer for realizing favorable morphology in efficient non-fullerene acceptor-based solar cells', Small, 10 4658-4663 (2014)

A study was conducted to design and investigate non-fullerene-based polymer solar cells (PSCs) singly-linked perylene bisimide dimmers (SDIPBI) acceptor and PBDTBDD as donor polym... [more]

A study was conducted to design and investigate non-fullerene-based polymer solar cells (PSCs) singly-linked perylene bisimide dimmers (SDIPBI) acceptor and PBDTBDD as donor polymer. The HOMO and LUMO levels of PBDTBDD, PBDTTT-C-T and SDIPBI were measured under the same experimental conditions. X-ray diffraction (XRD) analysis was performed on spin-coated films of the blend films of PBDTBDD: SDIPBI processed with different solvents to investigate the solid microstructure. The PBDTBDD: SDIPBI film processed with ternary solvent showed a much stronger diffraction peak. Charge carrier mobilities of the blend films processed with different solvents were measured according to the space charge limited current (SCLC) model.

DOI 10.1002/smll.201401082
Citations Scopus - 65
2014 Xiao C, Jiang W, Li X, Hao L, Liu C, Wang Z, 'Laterally expanded rylene diimides with uniform branched side chains for solution-processed air stable n-channel thin film transistors', ACS Applied Materials and Interfaces, 6 18098-18103 (2014)

© 2014 American Chemical Society. Molecular packing motifs in solid states is the dominant factor affecting the n-channel organic field-effect transistors (OFETs). However, few sy... [more]

© 2014 American Chemical Society. Molecular packing motifs in solid states is the dominant factor affecting the n-channel organic field-effect transistors (OFETs). However, few systematic researches were performed in the different extensions of p-conjugated molecules with the uniform substitution effecting the molecular packing motifs. In this manuscript, OFET devices based on three latterally expanded rylene diimides end-functionalized with uniform 3-hexylundecyl substitution on the imide positions were systematically studied on the relationship of molecular stacking, film microstructure, and charge transport. As the p-conjugated systems expanded from doubly linked perylene diimide dimer (d-4CldiPDI, 1), triply linked perylene diimide dimer (t-4CldiPDI, 2), to hybrid array (NDI-PDI-NDI, 3), their corresponding molecular packing motifs exhibited a divide: the optimized molecular configuration became more planar and d (001) spacing distances became larger, which resulted in a larger p-p overlapping. Thus, an enhanced electron mobility was obtained. A typical n-channel field-effect characteristic was observed in thin film devices based on these molecules under ambient conditions. Especially, the hybrid system (3) with more planar and p-expanded aromatic backbone exhibited superior electron mobility approaching 0.44 cm2V-1s-1and on/off ratio of 106after optimal annealing in this study.

DOI 10.1021/am504984z
Citations Scopus - 9
2014 He B, Ren Z, Yan S, Wang Z, 'Large area uniformly oriented multilayer graphene with high transparency and conducting properties derived from highly oriented polyethylene films', Journal of Materials Chemistry C, 2 6048-6055 (2014)

In this study, well-ordered multilayer graphene has been obtained via highly oriented polyethylene (OPE) films. Optical microscopy (OM), atomic force microscopy (AFM), Raman laser... [more]

In this study, well-ordered multilayer graphene has been obtained via highly oriented polyethylene (OPE) films. Optical microscopy (OM), atomic force microscopy (AFM), Raman laser spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results indicated that the obtained graphene films were continuous and uniform in lattice orientation. Optical and electrical characterization of the prepared graphene revealed that the thin films are stable in air and exhibit better optical and electrical properties than that obtained from non-oriented polyethylene (nOPE). This journal is © the Partner Organisations 2014.

DOI 10.1039/c4tc00481g
Citations Scopus - 2
2014 Sun J, Lu X, Ishikawa M, Nakano Y, Zhang S, Zhao J, et al., 'Inclusion complexes of fullerenes with flexible tetrathiafulvalene derivatives bearing four aryls through sulfur bridges', Journal of Materials Chemistry C, 2 8071-8076 (2014)

© the Partner Organisations 2014. TTF derivatives decorated with four aryls through the sulfur bridges are employed to form the donor-acceptor type inclusion complexes with fuller... [more]

© the Partner Organisations 2014. TTF derivatives decorated with four aryls through the sulfur bridges are employed to form the donor-acceptor type inclusion complexes with fullerenes. The key factor for the formation of inclusion complexes is the introduction of structural flexibility in TTF molecules along with the molecular size matching with fullerenes. A crystallographic study indicates that the structures of the resulting complexes are stabilized by a multidimensional intermolecular interaction network consisting of TTF cores, peripheral aryls, and fullerenes, which in turn gives rise to the electronic communication between the donor and the acceptor as proved by the solid state absorption spectra. Moreover, the fullerene molecules form the two-dimensional sheet structure in the complexes. This journal is

DOI 10.1039/c4tc01362j
Citations Scopus - 10
2014 Li C, Jiang W, Zhu X, Wang Z, 'Synthesis and properties of diazapentacene diimides', Asian Journal of Organic Chemistry, 3 114-117 (2014)

Diazapentacene diimides were prepared by the double cross-coupling of zirconacyclopentadienes with unilateral dibromonaphthalene diimide derivatives, and subsequent dehydrogenativ... [more]

Diazapentacene diimides were prepared by the double cross-coupling of zirconacyclopentadienes with unilateral dibromonaphthalene diimide derivatives, and subsequent dehydrogenative aromatization of the resulting dihydrodiazapentacene diimides. The optical and electrical properties of this series of diazapentacene diimides have high electron affinity (up to 4.39eV) and significantly smaller HOMO-LUMO gaps (as small as 1.26eV). Those diimides with wide absorption bands and small band-gaps are promising candidates for n-type semiconductors and NIR dyes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/ajoc.201300195
Citations Scopus - 9
2014 Wang Z, Bush RT, Sullivan LA, Chen C, Liu J, 'Selective oxidation of arsenite by peroxymonosulfate with high utilization efficiency of oxidant', Environmental Science and Technology, 48 3978-3985 (2014) [C1]

Oxidation of arsenite (As(III)) is a critical yet often weak link in many current technologies for remediating contaminated groundwater. We report a novel, efficient oxidation rea... [more]

Oxidation of arsenite (As(III)) is a critical yet often weak link in many current technologies for remediating contaminated groundwater. We report a novel, efficient oxidation reaction for As(III) conversion to As(V) using commercial available peroxymonosulfate (PMS). As(III) is rapidly oxidized by PMS with a utilization efficiency larger than 90%. Increasing PMS concentrations and pH accelerate oxidation of As(III), independent to the availability of dissolved oxygen the addition of PMS enables As(III) to oxidize completely to As(V) within 24 h, even in the presence of high concentrations of radical scavengers. On the basis of these observations and theoretical calculations, a two-electron transfer (i.e., oxygen atom transfer) reaction pathway is proposed. Direct oxidation of As(III) by PMS avoids the formation of nonselective reactive radicals, thus minimizing the adverse impact of coexisting organic matter and maximizing the utilization efficiency of PMS therefore, this simple approach is considered a cost-effective water treatment method for the oxidation of As(III) to As(V). © 2014 American Chemical Society.

DOI 10.1021/es405143u
Citations Scopus - 37Web of Science - 33
Co-authors Richard Bush
2014 Liu R, Guo Y, Wang Z, Liu J, 'Iron species in layered clay: Efficient electron shuttles for simultaneous conversion of dyes and Cr(VI)', Chemosphere, 95 643-646 (2014) [C1]

The simultaneous reduction of Chromium(VI) (Cr(VI)) and oxidation of cationic dyes in dispersions of Montmorillonite K10 (MK10) were examined under visible irradiation (¿ 420 nm).... [more]

The simultaneous reduction of Chromium(VI) (Cr(VI)) and oxidation of cationic dyes in dispersions of Montmorillonite K10 (MK10) were examined under visible irradiation (¿ 420 nm). The iron species (i.e. iron oxides, structural iron and exchangeable interlayer iron) in layered clays are active for catalytically reducing Cr(VI) by using Malachite green (MG) and Rhodamine B (RhB) as the electron donors. Molecular oxygen does not have a significant effect on clay-catalyzed Cr(VI) reduction, but is important for oxidative degradation of dye pollutants. MK10 catalysts are stable and reusable, and are therefore considered as a promising naturally-abundant material for decontamination of dye and heavy metals. © 2013 Elsevier Ltd.

DOI 10.1016/j.chemosphere.2013.09.055
Citations Scopus - 14Web of Science - 12
2014 Xiao D, Guo Y, Lou X, Fang C, Wang Z, Liu J, 'Distinct effects of oxalate versus malonate on the iron redox chemistry: Implications for the photo-Fenton reaction', Chemosphere, 103 354-358 (2014) [C1]

The dicarboxylic acids oxalate (Oxal) and malonate (Mal) are frequently detected as the final low-molecular-weight organic acids during oxidative degradation of aromatic compounds... [more]

The dicarboxylic acids oxalate (Oxal) and malonate (Mal) are frequently detected as the final low-molecular-weight organic acids during oxidative degradation of aromatic compounds. Here a distinct effect of Oxal versus Mal on iron-based photocatalytic technologies was reported by testing the degradation efficiency of the dye rhodamine B. The rates of dye degradation in irradiated Fe(III) solutions depended on Fe(III/II) speciation, photoreactivities of Fe complexes and reactivities of Fe(II) complexes with H2O2. Photolysis of the Fe(III)-oxalato complex was favorable due to the formation of O2-, HO2 andOH for oxidizing the dye; however, an excess of H2O2could quench the excited state of ferrioxalate, decreasing the degradation efficiency. In contrast, activities of UV/Fe(III) in the presence of Mal were significantly diminished because Fe(III)-Mal complexes, with much lower quantum yield of Fe(II) from photoreduction, dominated Fe(III) speciation. The results provide data for an understanding of the mechanism of iron redox (photo)chemistry mediated by diacids, which will aid in selecting appropriate Fe ligands, screening photo-Fenton conditions and designing UV/Fe(III) treatability. © 2013 Elsevier Ltd.

DOI 10.1016/j.chemosphere.2013.11.069
Citations Scopus - 14Web of Science - 10
2014 Yuan R, Wang Z, Hu Y, Wang B, Gao S, 'Probing the radical chemistry in UV/persulfate-based saline wastewater treatment: Kinetics modeling and byproducts identification', Chemosphere, 109 106-112 (2014) [C1]

The effect of Cl-on the oxidative degradation of Acid Orange 7 (AO7) was investigated in UV/S2O82-system to elucidate the chlorination pathways in saline wastewaters. Lower amount... [more]

The effect of Cl-on the oxidative degradation of Acid Orange 7 (AO7) was investigated in UV/S2O82-system to elucidate the chlorination pathways in saline wastewaters. Lower amount of Cl-as well as Br-enhanced the decoloration of AO7, but such promotion effect reduced gradually with the increasing halide ion dosage. The dye mineralization was found to be inhibited by Cl-, especially under acidic conditions. Results of kinetics modeling demonstrated that the fraction of different oxidizing radicals largely depended on the content of Cl-. At the initial pH of 6.5, Cl2-was much more abundant than SO4-. The significance of Cl2-for AO7 degradation increased with the increasing Cl-concentration and overwhelmed that of SO4-at [Cl-]>1mM. Without Cl-, SO4-was the predominant radical for AO7 degradation under acidic conditions, whileOH prevailed gradually at higher pH. Under high salinity conditions, moreOH can be formed and contributed to the dye degradation especially in alkaline medium, leading to higher destruction efficiency of AO7. Several chlorinated byproducts were detected in the presence of chloride ions, and SO4-/Cl2--based degradation pathways of AO7 were proposed. This work provides further understanding of the complex reaction mechanisms for SO4--based advanced oxidation processes in chloride-rich environments. © 2014 Elsevier Ltd.

DOI 10.1016/j.chemosphere.2014.03.007
Citations Scopus - 35Web of Science - 35
2014 Lou X, Wu L, Guo Y, Chen C, Wang Z, Xiao D, et al., 'Peroxymonosulfate activation by phosphate anion for organics degradation in water', Chemosphere, 117 582-585 (2014) [C1]

© 2014 Elsevier Ltd. Activation of peroxygens is a critical method to generate oxidative species, but often consumes additional chemical reagents and/or energy. Here we report a n... [more]

© 2014 Elsevier Ltd. Activation of peroxygens is a critical method to generate oxidative species, but often consumes additional chemical reagents and/or energy. Here we report a novel and efficient activation reaction for peroxymonosulfate (PMS) by phosphate anions (PBS). The PBS/PMS coupled system, at neutral pH, is able to decompose efficiently even mineralize a variety of organic pollutants, such as Acid Orange 7, Rhodamine B and 2,4,6-trichlorophenol. In contrast, no measurable degradation was observed when the PMS was replaced by other peroxygens (i.e. hydrogen peroxide and peroxydisulfate). Both PMS and PBS are indispensable for the oxidative degradation of pollutants. Increasing pH and concentrations of PMS and PBS significantly accelerate the degradation of organics. It is proposed that OH would be the major radical for contamination degradation at pH 7.0 through the radical quenching experiments. This work provides a new way of PMS activation for decontamination at neutral pH, in particular for phosphate-rich wastewater treatment.

DOI 10.1016/j.chemosphere.2014.09.046
Citations Scopus - 40Web of Science - 34
2014 Wang H, Zhang L, Chen Z, Hu J, Li S, Wang Z, et al., 'Semiconductor heterojunction photocatalysts: Design, construction, and photocatalytic performances', Chemical Society Reviews, 43 5234-5244 (2014)

Semiconductor-mediated photocatalysis has received tremendous attention as it holds great promise to address the worldwide energy and environmental issues. To overcome the serious... [more]

Semiconductor-mediated photocatalysis has received tremendous attention as it holds great promise to address the worldwide energy and environmental issues. To overcome the serious drawbacks of fast charge recombination and the limited visible-light absorption of semiconductor photocatalysts, many strategies have been developed in the past few decades and the most widely used one is to develop photocatalytic heterojunctions. This review attempts to summarize the recent progress in the rational design and fabrication of heterojunction photocatalysts, such as the semiconductor-semiconductor heterojunction, the semiconductor-metal heterojunction, the semiconductor-carbon heterojunction and the multicomponent heterojunction. The photocatalytic properties of the four junction systems are also discussed in relation to the environmental and energy applications, such as degradation of pollutants, hydrogen generation and photocatalytic disinfection. This tutorial review ends with a summary and some perspectives on the challenges and new directions in this exciting and still emerging area of research. This journal is © the Partner Organisations 2014.

DOI 10.1039/c4cs00126e
Citations Scopus - 1007Web of Science - 966
2014 Wang Z, Liu J, 'New insight into photochemical oxidation of Fe(II): The roles of Fe(III) and reactive oxygen species', Catalysis Today, 224 244-250 (2014) [C1]

Photooxidation of Fe(II) at acidic pH occurs in photocatalytic processes of Fe(III) species, but its reaction mechanism is not well understood. The kinetics of Fe(II) oxidation in... [more]

Photooxidation of Fe(II) at acidic pH occurs in photocatalytic processes of Fe(III) species, but its reaction mechanism is not well understood. The kinetics of Fe(II) oxidation in irradiated aqueous solutions at pH 3.0 have been investigated in terms of kinetic modeling approach, rate constant estimation and the significance of various oxidation pathways. Fe(II) oxidation kinetics strongly rely on the availability of UV light, Fe(III) ions and oxygen. The presence of a portion of Fe(III) in Fe(II)-containing solutions favors the rapid oxidation of Fe(II). At high concentration of Fe(II), excitation of Fe(III) species may be quenched by Fe(II) in deaerated systems or may sensitize Fe(II) oxygenation under oxic conditions. By incorporation of this photosensitization pathway, the established model in this study is shown to be able to adequately describe the oxidation of Fe(II) at pH 3.0. Sensitivity analysis indicates that photolysis of Fe(III) species is critically important for overall Fe(II) oxidation kinetics. Fe(III)-catalyzed oxygenation of Fe(II), and oxidation of Fe(II) by HO2and OH also exerts a marked impact on the oxidation of Fe(II). Therefore, Fe(III)-catalyzed oxygen activation and their secondary reactive oxygen species (ROS) account for the oxidation kinetics of Fe(II) at acidic pH. © 2013 Elsevier B.V.

DOI 10.1016/j.cattod.2013.09.063
Citations Scopus - 4Web of Science - 3
2014 Wang Z, Xiao D, Liu R, Guo Y, Lou X, Liu J, 'Fenton-like degradation of reactive dyes catalyzed by biogenic jarosite', Journal of Advanced Oxidation Technologies, 17 104-108 (2014)

A kind of Fe mineral-biogenic jarosite was prepared by biooxidation of Fe2+ using Acidithiobacillus ferrooxidans. Decolorization of reactive dyes, Reactive Blue 19 (RB) and Reacti... [more]

A kind of Fe mineral-biogenic jarosite was prepared by biooxidation of Fe2+ using Acidithiobacillus ferrooxidans. Decolorization of reactive dyes, Reactive Blue 19 (RB) and Reactive Orange 1 (RO), were conducted using asprepared jarosite as a catalyst in the presence of H2O2 via a Fenton-like reaction process. The experimental results indicated that jarosite can serve as an efficient Fe catalyst to initiate Fenton-like reaction in the process of dye decolorization. 98% of decolorization efficiency of RB was achieved within 105 min of reaction time by using 5 mM H2O 2 and 1 g/L jarosite catalyst at pH 5.0. The current investigation may provide a practical and costseffective way using biogenic Fe minerals for remediation of wastewater contaminated with industrial colorants. © 2014 Science &Technology Network, Inc.

DOI 10.1515/jaots-2014-0114
Citations Scopus - 5Web of Science - 5
2014 Guo Y, Zhou J, Lou X, Liu R, Xiao D, Fang C, et al., 'Enhanced degradation of Tetrabromobisphenol A in water by a UV/base/persulfate system: Kinetics and intermediates', Chemical Engineering Journal, 254 538-544 (2014) [C1]

Tetrabromobisphenol A (TBBPA), one of the most frequently used brominated flame retardants (BFRs), is only soluble in strongly alkaline solutions where most advanced oxidation pro... [more]

Tetrabromobisphenol A (TBBPA), one of the most frequently used brominated flame retardants (BFRs), is only soluble in strongly alkaline solutions where most advanced oxidation processes (AOPs) are inefficient or in organic solvents. It is highly desirable to develop an environmentally friendly cleanup technology for TBBPA which operates at alkaline pH without the need of organic solvents to enhance its solubility in water. In this study a favorable UV/base/persulfate (PS) system for rapid degradation of TBBPA in aqueous solution is reported. Increases of initial pH and PS concentrations have positive effects on the degradation of TBBPA and a high initial TBBPA concentration has a negative influence. The addition of Br- has a negligible effect on the degradation of TBBPA. The low TOC removal and degradation intermediates of TBBPA identified by GC-MS suggested that TBBPA was degraded via the cleavage between the isopropyl group and one of the benzene rings rather than complete debromination and degradation. The present study provides a simple and green approach to detoxify TBBPA in water rather than using toxic organic solvents. © 2014 Elsevier B.V.

DOI 10.1016/j.cej.2014.05.143
Citations Scopus - 39Web of Science - 34
2014 Liu R, Xiao D, Guo Y, Wang Z, Liu J, 'A novel photosensitized Fenton reaction catalyzed by sandwiched iron in synthetic nontronite', RSC Advances, 4 12958-12963 (2014)

The conventional photo-Fenton reaction often suffers from the constraints of operation pH, low iron loading, ultraviolet availability in solar light and instability of iron-based ... [more]

The conventional photo-Fenton reaction often suffers from the constraints of operation pH, low iron loading, ultraviolet availability in solar light and instability of iron-based catalysts. Here we report a novel heterogeneous Fenton reaction which works with a dye-photosensitized structural Fe(iii)/Fe(ii) redox cycling mechanism. The synthesized nontronite catalyst (NAU) was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS) analysis, and thermal gravimetric analysis (TG). NAU exhibited excellent catalytic activity over a wide pH range (3.0-8.0) for highly efficient degradation of Rhodamine B by hydrogen peroxide (H2O2) under visible light irradiation (¿ > 420 nm). The excited dye molecule donates electrons to structural iron sandwiched in NAU which further catalyzes H2O2 to generate highly reactive OH radicals. This iron-rich clay mineral (total Fe, 24.4 wt%) is chemically and mechanically stable. There are no measurable iron leaching, nor any noticeable loss of activity and damage to the clay structure observed after 6 recycles. Therefore, NAU clay has outstanding merits for the practical treatment of organic dye pollutants at large scale. This journal is © the Partner Organisations 2014.

DOI 10.1039/c3ra47359g
Citations Scopus - 11Web of Science - 11
2014 Wang Z, 'Probing the importance of planar surfaces and crystal edges for electron transfer within iron-bearing clays', RSC Advances, 4 31476-31480 (2014)

We demonstrated the importance of basal planes and crystal edge for electron transfer within montmorillonite (MK10) and nontronite (NAu-2) by a facile dye-sensitized photoreductio... [more]

We demonstrated the importance of basal planes and crystal edge for electron transfer within montmorillonite (MK10) and nontronite (NAu-2) by a facile dye-sensitized photoreduction method. It was found that not all structural Fe in the clay matrix was redox-active. The results are vital to the utilization of naturally abundant clays in environmental redox chemistry. This journal is © the Partner Organisations 2014.

DOI 10.1039/c4ra04521a
Citations Scopus - 2Web of Science - 2
2014 Wang Z, Xiao D, Liu J, 'Diverse redox chemistry of photo/ferrioxalate system', RSC Advances, 4 44654-44658 (2014)

© 2014 the Partner Organisations. The diverse redox processes of the photo/ferrioxalate system (PFS) were investigated by varying the concentrations of Fe(iii), oxalate and oxygen... [more]

© 2014 the Partner Organisations. The diverse redox processes of the photo/ferrioxalate system (PFS) were investigated by varying the concentrations of Fe(iii), oxalate and oxygen. Photoreactivity of PFS is determined by the prevalence of the most photolabile Fe(iii) and abundance of Fe(iii) and oxalate, which is critical for the operation optimization of PFS in wastewater treatment.

DOI 10.1039/c4ra07153k
Citations Scopus - 7Web of Science - 6
2014 Zhou S, Li Y, Chen J, Liu Z, Wang Z, Na P, 'Enhanced Cr(vi) removal from aqueous solutions using Ni/Fe bimetallic nanoparticles: Characterization, kinetics and mechanism', RSC Advances, 4 50699-50707 (2014)

© the Partner Organisations 2014. In this study, Ni/Fe bimetallic nanoparticles were prepared by a liquid-phase chemical reduction method and characterized by scanning electron mi... [more]

© the Partner Organisations 2014. In this study, Ni/Fe bimetallic nanoparticles were prepared by a liquid-phase chemical reduction method and characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS) with image mapping, transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The as-prepared Ni/Fe material was applied to remove Cr(vi) via a coupled adsorption/reduction process. It was found that Cr(vi) removal followed pseudo-second-order reaction kinetics. Acidic pH favored the efficient removal of Cr(vi) due to the abundance of reactive H species that were mediated by the Ni catalyst. XPS studies demonstrated that Cr(vi) removal on the surface of the bimetallic nanoparticles was a synergistic adsorption and reduction process. The introduction of nickel to nZVI not only controls iron passivation but also facilitates the efficient flow of electron transfer between iron and Cr(vi), and thus the efficient reduction of Cr(vi) to Cr(iii). Hydroxylated Cr(OH)3 and co-precipitation of CrxFe1-x(OH)3 were the final products of Cr(vi) removal by the Ni/Fe material. This journal is

DOI 10.1039/c4ra08754b
Citations Scopus - 21
2013 Wu Y, Zhen Y, Wang Z, Fu H, 'Donor-linked di(perylene bisimide)s: Arrays exhibiting fast electron transfer for photosynthesis mimics', Journal of Physical Chemistry A, 117 1712-1720 (2013)

The first example of donor-linked di(perylene bisimide)s is reported. UV-vis absorption spectra of these newly synthesized dyads showed intense absorption across the entire visibl... [more]

The first example of donor-linked di(perylene bisimide)s is reported. UV-vis absorption spectra of these newly synthesized dyads showed intense absorption across the entire visible region, demonstrating their excellent light-harvesting activities. The severe fluorescence quenching event probed by steady-state fluorescence spectroscopy and the free-energy calculations suggested the possibility of electron transfer (ET) in these arrays upon photoexcitation. Further femtosecond transient absorption spectra clarified that the fluorescence quenching was due to fast intramolecular ET. The rate of the charge separation (CS) was found to be as high as 1012 s-1 in CH2Cl2. It was suggested that the large ET driving forces, strong donor-acceptor electronic coupling, and relatively small reorganization energy of diPBI accounted for the rapid ET process in a synergic manner. The fate of the generated radical ion pair depended on the solvent used. Rapid charge recombination to ground state occurred for the dyads in polar CH2Cl2 and for diPBI-TPA in nonpolar toluene. However, sufficient 3diPBI* population was attained via efficient spin-orbit coupled intersystem crossing from the charge-separated state for diPBI-PdTPP in toluene. These photophysical properties are interpreted as the cooperation between thermodynamic feasibility and kinetic manipulation. © 2013 American Chemical Society.

DOI 10.1021/jp310838w
Citations Scopus - 10
2013 Wang XY, Jiang W, Chen T, Yan HJ, Wang ZH, Wan LJ, Wang D, 'Molecular evidence for the intermolecular S¿S interaction in the surface molecular packing motifs of a fused thiophene derivative', Chemical Communications, 49 1829-1831 (2013)

A microscopic investigation of the molecular packing structures of a fused thiophene derivative reveals the important role of intermolecular S¿S interaction in directing the 2D se... [more]

A microscopic investigation of the molecular packing structures of a fused thiophene derivative reveals the important role of intermolecular S¿S interaction in directing the 2D self-assembly. Thermal annealing of the assembly results in the irreversible phase transition to a new structure with different molecular trimeric packing motifs. © 2013 The Royal Society of Chemistry.

DOI 10.1039/c3cc37990f
Citations Scopus - 19
2013 Cui Y, Wu Y, Liu Y, Yang G, Liu L, Fu H, et al., 'PEGylated nanoparticles of diperylene bisimides with high efficiency of

Diperylene bisimide bearing poly(ethylene glycol) chains (PEG-diPBI) were synthesized using click coupling reaction between mono-azido terminated PEG 113 and bis-alkynyl functiona... [more]

Diperylene bisimide bearing poly(ethylene glycol) chains (PEG-diPBI) were synthesized using click coupling reaction between mono-azido terminated PEG 113 and bis-alkynyl functionalized diPBI. Then the PEG-diPBI self-assembled into micelles in water, which were characterized by cryo-TEM, UV-Vis spectrometry and fluorescence spectrometry. Furthermore, the PEG-diPBI was applied by continuous photolysis procedure, the result showed a broad absorption and very high efficiency of 1O2 generation (F¿ = 0.66). Moreover, the uptake of PEG-diPBI particles by human bladder carcinoma EJ cells was observed by confocal laser scanning microscopy. Also, phototoxicity experiment result was applied to PEG-diPBI, and gave the result that it is worth to investigate the properties of PEG-diPBI particles for photodynamic therapy. © 2012 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.dyepig.2012.12.008
Citations Scopus - 15
2013 Kang H, Jiang W, Wang Z, 'Construction of well-defined butadiynylene-linked perylene bisimide arrays via cross-coupling', Dyes and Pigments, 97 244-249 (2013)

A homogeneous series of well-defined oligo-butadiynylene-PBIs have been efficiently synthesized in one pot by Hay Cross-Coupling. It is shocked that the rate of this oxidative cou... [more]

A homogeneous series of well-defined oligo-butadiynylene-PBIs have been efficiently synthesized in one pot by Hay Cross-Coupling. It is shocked that the rate of this oxidative coupling reaction is very fast, the whole process just takes a short time no more than 10 s. The four butadiynylene-linked oligomers having good solubility in common solvents show absorption spectra with broad absorption range (from 300 nm to 650 nm) and gradually increasing absorption coefficients (up to 1.4 × 105mol-1cm-1). From the cyclic voltammentry data, we can see that the LUMO levels are effectively and precisely tuned by embedding butadiynylene linkage between PBI subunits. These compounds are promising for potential applications in molecular electronic devices such as conducting molecular wires and solar cells. © 2012 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.dyepig.2012.12.015
Citations Scopus - 12
2013 Kang H, Zheng YQ, Jiang W, Xiao C, Wang JY, Pei J, Wang Z, 'All-polymer solar cells based on PTACs/P3HT blends with large open-circuit voltage', Dyes and Pigments, 99 1065-1071 (2013)

Four D-A polymers alternated between 3,4,9,10-tetra(n-alkoxy-carbonyl)- perylenes (PTACs) and thiophene derivatives (TT and BDT) in backbones were synthesized under Stille couplin... [more]

Four D-A polymers alternated between 3,4,9,10-tetra(n-alkoxy-carbonyl)- perylenes (PTACs) and thiophene derivatives (TT and BDT) in backbones were synthesized under Stille coupling conditions. Their structures were unambiguously verified by1H NMR and elemental analysis. These polymers showed high-lying LUMO energy levels of about -3.50 eV due to the less electron deficient characteristics of PTACs units. All-polymer solar cells based on these PTAC-based polymers as acceptor and P3HT as donor have been fabricated. With annealing at 100 C for 15 min, P4/P3HT blends demonstrated a power conversion efficiency of up to 1.10% with a short circuit current (JSC) of 2.9 mA/cm2, an open circuit voltage (VOC) 0.92 V, and a fill factor (FF) of 0.40, illustrating that PTACs are attractive candidates for solar cells. © 2013 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.dyepig.2013.08.017
Citations Scopus - 9
2013 Jiang W, Li Y, Wang Z, 'Heteroarenes as high performance organic semiconductors', Chemical Society Reviews, 42 6113-6127 (2013)

The design, synthesis, and characterization of new organic semiconductors (OSCs) are important aspects for the development of next-generation optoelectronic devices. Structurally,... [more]

The design, synthesis, and characterization of new organic semiconductors (OSCs) are important aspects for the development of next-generation optoelectronic devices. Structurally, organic semiconductors based on p-conjugated molecules can be easily modified via rational synthesis to tune multi-level self-assembled structures and discover novel chemical, optical, and electronic properties. Heteroarenes, which contain chalcogens and nitrogens in fused aromatic rings, are being developed as promising semiconducting materials for applications in a variety of electronic devices due to their outstanding optoelectronic properties. We highlight recent approaches toward realizing high performance p-channel field effect transistors based on linear heteroacenes and heteroatom annulated polycyclic aromatics (PAHs) as key functional components. These comprehensive, but carefully orchestrated approaches simultaneously address (i) practical synthesis, (ii) tunable self-assembled packing arrangement as well as (iii) high electronic performance. © 2013 The Royal Society of Chemistry.

DOI 10.1039/c3cs60108k
Citations Scopus - 198
2013 Jiang X, Liao Q, Zhou J, Wang Z, Chan C, Li L, 'Relaxation dynamics of stretched polymer chains traced by shear induced Shish-Kebab structure', Journal of Polymer Science, Part B: Polymer Physics, 51 907-914 (2013)

We have developed a morphologic method to investigate the relaxation processing of the stretched polymer chains in melts, in which an atomic force microscope probe was used to she... [more]

We have developed a morphologic method to investigate the relaxation processing of the stretched polymer chains in melts, in which an atomic force microscope probe was used to shear the surface of an isotactic polypropylene melt to obtain the isolated shish-kebab structure. We present the results of the time dependence of length of the isolated shish-kebab structure and the stress dependence of the kebab density along the direction of shish in this paper. Our results demonstrate that the shear-oriented polymer melts show the relaxation dynamics of worm-like chain where the length deficit of the isolated shish-kebab structure is scaled with the relaxation time as a power of 1/3. The melting behavior of shish-kebab structure was also investigated. © 2013 Wiley Periodicals, Inc.

DOI 10.1002/polb.23281
Citations Scopus - 5
2013 Cui Y, Yan Y, Chen Y, Wang Z, 'Dibromomaleimide derivative as an efficient polymer coupling agent for building topological polymers', Macromolecular Chemistry and Physics, 214 470-477 (2013)

The dibromomaleimide derivative, N-(4-bromobutyl)-dibromomaleimide (dBMIB), is found to be a highly efficient coupling agent to dimerize thiol-terminated hydrophilic polymers by s... [more]

The dibromomaleimide derivative, N-(4-bromobutyl)-dibromomaleimide (dBMIB), is found to be a highly efficient coupling agent to dimerize thiol-terminated hydrophilic polymers by substituent reaction. When mono-thiol poly(ethylene oxide) (PEO45-SH) is mixed with dBMIB in an equivalent molar feed in water, a dimer of PEO45with a maleimide unit located at the chain center, (PEO45)2MIB, is obtained quantitatively. The dBMIB is also used to dimerize thiol- terminated poly(N-(2-acryloyloxyethyl) pyrrolidone) and poly(N,N-dimethyl acrylamide). Moreover, the butylene bromide of (PEO45)2MIB is transferred into a butylene azide, which is allowed to react with alkynyl-terminated polystyrene to give a A2B miktoarm star polymer via a copper-catalyzed azide-alkyne cycloaddition coupling reaction. Thiol-terminated synthetic polymer chains may be dimerized by a dibromomaleimide derivative via an efficient substituent reaction. The new polymer bearing an alkyl bromide is further applied for coupling another polymer by click reaction to form star polymers. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/macp.201200614
Citations Scopus - 10
2013 Li C, Xiao C, Li Y, Wang Z, 'Synthesis and properties of heterocyclic acene diimides', Organic Letters, 15 682-685 (2013)

A series of heterocyclic acene diimides were synthesized effectively based on the condensation of o-phenylenediamine, 1,2-benzenedithiol, and 2-aminothiophenol with 2,3,6,7-tetrab... [more]

A series of heterocyclic acene diimides were synthesized effectively based on the condensation of o-phenylenediamine, 1,2-benzenedithiol, and 2-aminothiophenol with 2,3,6,7-tetrabromo-1,4,5,8-naphthalene tetracarboxylic diimide. The diimides exhibit interesting optical and electrical properties with one of them showing a hole mobility up to 0.02 cm2 V-1 s-1. © 2013 American Chemical Society.

DOI 10.1021/ol303551p
Citations Scopus - 36
2013 Gao J, Li Y, Wang Z, 'Synthesis and properties of naphthobisbenzothiophene diimides', Organic Letters, 15 1366-1369 (2013)

Laterally extended naphthalene diimides composed of naphthobisbenzothiophene skeleton and two imide groups were synthesized, which exhibit interesting packing arrangements and opt... [more]

Laterally extended naphthalene diimides composed of naphthobisbenzothiophene skeleton and two imide groups were synthesized, which exhibit interesting packing arrangements and optoelectrical properties. © 2013 American Chemical Society.

DOI 10.1021/ol400324w
Citations Scopus - 27
2013 Liu H, Wu Y, Wang Z, Fu H, 'High performance Langmuir-Schaeffer film transistors based on air stable n-type diperylene bisimide', Organic Electronics: physics, materials, applications, 14 2610-2616 (2013)

Diperylene Bisimide (DIPP-diPBI) mono- and/or multi-layer film using Langmuir-Schaeffer (LS) techniques has been fabricated and the OFET device performance based on the as-prepare... [more]

Diperylene Bisimide (DIPP-diPBI) mono- and/or multi-layer film using Langmuir-Schaeffer (LS) techniques has been fabricated and the OFET device performance based on the as-prepared LS film is investigated. The thickness of monolayer film is determined to be 2.3 nm by using atomic force microscopy, which is closely matched with the interplanar spacing estimated from the XRD spectra. The length of molecular long axis is measured to be 21.9 Å from the DFT optimized configuration, indicating that the long axis of molecule in LS film approximately stands upright on hydrophobic substrates. The absorption maximum at 417 nm shows a good linear corrleation with the layer number, proving the obtained films are deposited in a layer-by-layer fassion. The film with precision control of the long-range order and lateral packing density by LS deposition exhibits good electron injection properties and high FET device performance. The charge transport behavior is also investigated as a function of the layer number of LS film. The electron mobility gradually increases with the number of layers and saturates at a plateau with a mean value of 0.03 cm2V-1s-1in the atmosphere upon completion of the first eight layers. It is a direct evidence of physical size of charge transport layer. Furthermore, the fabricated FET device exhibits long-time stability in the air. The integration of LS method with air stability of the n-type compound affords an opportunity to explore solution-phase self-assembly and electronic devices fabrication with controllable molecular layers. © 2013 Elsevier B.V.

DOI 10.1016/j.orgel.2013.05.021
Citations Scopus - 6
2013 Zhang J, Tan L, Jiang W, Hu W, Wang Z, 'N-Alkyl substituted di(perylene bisimides) as air-stable electron transport materials for solution-processible thin-film transistors with enhanced performance', Journal of Materials Chemistry C, 1 3200-3206 (2013)

We present here the synthesis, characterization, and thin film transistor performance of six semiconducting materials by alkyl substitution on the N-positions of tetrachlorinated ... [more]

We present here the synthesis, characterization, and thin film transistor performance of six semiconducting materials by alkyl substitution on the N-positions of tetrachlorinated di(perylene bisimide) (4CldiPBI). Although the different alkyl chain substituents have a negligible effect on the absorption maximum and energy gap, the DSC thermal behaviour and electron performance are sensitive to the length of the alkyl chains. Substitution with the longer alkyl chains produced higher electron mobilities in air. C18-4CldiPBI (6), which exhibited the best solubility in common organic solvents, has demonstrated excellent thin film electron performance in air with the mobility as high as 0.70 cm2V-1s-1and a high on/off ratio of 4 × 107. Furthermore, the device performance showed good stability in air for months without apparent degradation. © The Royal Society of Chemistry 2013.

DOI 10.1039/c3tc30156g
Citations Scopus - 29
2013 Li X, Xiao C, Jiang W, Wang Z, 'High-performance electron-transporting hybrid rylenes with low threshold voltage', Journal of Materials Chemistry C, 1 7513-7518 (2013)

We present here a new family of hybrid rylene arrays (3a-d) by the combination of Stille coupling and C-H transformation via a facile one-pot synthesis. The p-expanded rylene diim... [more]

We present here a new family of hybrid rylene arrays (3a-d) by the combination of Stille coupling and C-H transformation via a facile one-pot synthesis. The p-expanded rylene diimides exhibit broadened and intensive optical absorption accompanied by higher electron affinity. The linear alkyl chain substituted NDI-diPDI-NDI (3b) revealed its electron transporting characteristics with good air stability and low threshold voltage. © 2013 'The Royal Society of Chemistry.

DOI 10.1039/c3tc31644k
Citations Scopus - 10
2013 Hao L, Xiao C, Zhang J, Jiang W, Xu W, Wang Z, 'Perpendicularly entangled perylene diimides for high performance electron transport materials', Journal of Materials Chemistry C, 1 7812-7818 (2013)

A new family of perpendicularly entangled perylene diimides and di(perylene diimide) dimers featuring double linkage was synthesized via copper-mediated Ullmann coupling. The high... [more]

A new family of perpendicularly entangled perylene diimides and di(perylene diimide) dimers featuring double linkage was synthesized via copper-mediated Ullmann coupling. The highly twisting structures endow them remarkable electron transport characteristics with comparable mobility reaching 0.16 cm2V-1s-1and an on/off current ratio up to 5.0 × 106in air for PDI dimer based solution-processed OTFTs. While diPDI dimers with expanded conjugated core proved their competing electron mobilities as PDI dimers, especially for their low threshold voltage and good air stability. © 2013 The Royal Society of Chemistry.

DOI 10.1039/c3tc31912a
Citations Scopus - 9
2013 Lu X, Dong H, He P, Zhang X, Liu J, Meng Q, et al., 'A Ligand-free Copper-promoted Dimerization of Perylene Bisimide by Aromatic C-C Homocoupling and C-H Activation', Asian Journal of Organic Chemistry, 2 558-560 (2013)
DOI 10.1002/ajoc.201300109
Citations Scopus - 2
2013 Wang Z, Bush RT, Sullivan LA, Liu J, 'Simultaneous redox conversion of chromium(VI) and arsenic(III) under acidic conditions', Environmental Science and Technology, 47 6486-6492 (2013) [C1]

Arsenic and chromium are often abundant constituents of acid mine drainage (AMD) and are most harmful as arsenite (As(III)) and hexavalent (Cr(VI)). To simultaneously change their... [more]

Arsenic and chromium are often abundant constituents of acid mine drainage (AMD) and are most harmful as arsenite (As(III)) and hexavalent (Cr(VI)). To simultaneously change their oxidation state from As(III) to As(V), and Cr(VI) to Cr(III), is a potentially effective and attractive strategy for environmental remediation. The coabundance of As(III) and Cr(VI) in natural environments indicates their negligible direct interaction. The addition of H 2O2 enables and greatly accelerates the simultaneous oxidation of As(III) and reduction of Cr(VI). These reactions are further enhanced at acidic pH and higher concentrations of Cr(VI). However, the presence of ligands (i.e., oxalate, citrate, pyrophosphate) greatly retards the oxidation of As(III), even though it enhances the reduction of Cr(VI). To explain these results we propose a reaction mechanism where Cr(VI) is primarily reduced to Cr(III) by H2O2, via the intermediate tetraperoxochromate Cr(V). Cr(V) is then involved in the formation of ¿OH radicals. In the presence of ligands, the capacity of Cr(V) to form ¿OH radicals, which are primarily responsible for As(III) oxidation, is practically inhibited. Our findings demonstrate the feasibility for the coconversion of As(III) and Cr(VI) in AMD and real-world constraints to this strategy for environmental remediation. © 2013 American Chemical Society.

DOI 10.1021/es400547p
Citations Scopus - 37Web of Science - 33
Co-authors Richard Bush
2013 Guo Y, Lou X, Fang C, Xiao D, Wang Z, Liu J, 'Novel photo-sulfite system: Toward simultaneous transformations of inorganic and organic pollutants', Environmental Science and Technology, 47 11174-11181 (2013) [C1]

An efficient and green advanced oxidation process (i.e., photo-sulfite reaction) for the simultaneous oxidation of sulfite and organic pollutants in water is reported. The photo-s... [more]

An efficient and green advanced oxidation process (i.e., photo-sulfite reaction) for the simultaneous oxidation of sulfite and organic pollutants in water is reported. The photo-sulfite system (UV-Fe(III)-sulfite) is based on the Fe-catalyzed sulfite oxidation and photochemistry of Fe(III) species. SO 4¿- and ¿OH radicals were identified in the photo-sulfite system with radical scavenging experiments using specific alcohols. This novel technology was consistently proven to be more favorable than the alternative Fe(III)-sulfite systems for the degradation of 2,4,6-trichlorophenol (2,4,6-TCP) and other organic pollutants at all conditions tested. The reactivity of photo-sulfite system was sustained due to the spontaneous switch of photoactive species from Fe(III)-sulfito to Fe(III)-hydroxo complexes with the depletion of sulfite and the decrease in pH. In contrast, in the absence of light the performance of the Fe(III)-sulfite system was greatly diminished after the consumption of sulfite. The formation of the Fe(III)-sulfito complex is a necessary step for initiating the photo-sulfite reaction. Inhibition of the oxidation of 2,4,6-TCP and methyl orange (MO) was observed in the presence of ligands that can stabilize one or more of the reactants: Fe(III), Fe(II), or sulfite. Our study provides a new facile route for the generation of SO4¿- and simultaneous removal of organic and inorganic pollutants. © 2013 American Chemical Society.

DOI 10.1021/es403199p
Citations Scopus - 43Web of Science - 39
2013 Wang Z, Bush RT, Liu J, 'Arsenic(III) and iron(II) co-oxidation by oxygen and hydrogen peroxide: Divergent reactions in the presence of organic ligands', Chemosphere, 93 1936-1941 (2013) [C1]

Iron-catalyzed oxidation of As(III) to As(V) can be highly effective for toxic arsenic removal via Fenton reaction and Fe(II) oxygenation. However, the contribution of ubiquitous ... [more]

Iron-catalyzed oxidation of As(III) to As(V) can be highly effective for toxic arsenic removal via Fenton reaction and Fe(II) oxygenation. However, the contribution of ubiquitous organic ligands is poorly understood, despite its significant role in redox chemistry of arsenic in natural and engineered systems. In this work, selected naturally occurring organic ligands and synthetic ligands in co-oxidation of Fe(II) and As(III) were examined as a function of pH, Fe(II), H2O2, and radical scavengers (methanol and 2-propanol) concentration. As(III) was not measurably oxidised in the presence of excess ethylenediaminetetraacetic acid (EDTA) (i.e. Fe(II):EDTA<1:1), contrasting with the rapid oxidation of Fe(II) by O2 and H2O2 at neutral pH under the same conditions. However, partial oxidation of As(III) was observed at a 2:1 ratio of Fe(II):EDTA. Rapid Fe(II) oxidation in the presence of organic ligands did not necessarily result in the coupled As(III) oxidation. Organic ligands act as both iron speciation regulators and radicals scavengers. Further quenching experiments suggested both hydroxyl radicals and high-valent Fe species contributed to As(III) oxidation. The present findings are significant for the better understanding of aquatic redox chemistry of iron and arsenic in the environment and for optimization of iron-catalyzed arsenic remediation technology. © 2013 Elsevier Ltd.

DOI 10.1016/j.chemosphere.2013.06.076
Citations Scopus - 14Web of Science - 12
Co-authors Richard Bush
2013 Lou XY, Guo YG, Xiao DX, Wang ZH, Lu SY, Liu JS, 'Rapid dye degradation with reactive oxidants generated by chloride-induced peroxymonosulfate activation', Environmental Science and Pollution Research, 20 6317-6323 (2013)

Transition-metal is known to catalyze peroxymonosulfate (PMS) decomposition to produce sulfate radicals. Here we report reactions between PMS and chloride, without a need of trans... [more]

Transition-metal is known to catalyze peroxymonosulfate (PMS) decomposition to produce sulfate radicals. Here we report reactions between PMS and chloride, without a need of transition metals, also can be used to degrade organic dye pollutant (Rhodamine B, (RhB)). Some important operating parameters, such as dosages of PMS and Cl-, pH of solution, temperature, ionic strength, and several common cations, were systematically investigated. Almost complete decoloration of RhB was achieved within 5 min ([PMS] = 0.5 mM, [Cl-] = 120 mM, and pH 3.0), and RhB bleaching rate increased with the increased dosages of both PMS and chloride ion, following the pseudo-first-order kinetic model. However, the total organic carbon (TOC) removal results demonstrated that the decoloration of RhB was due to the destruction of chromophore rather than complete degradation. RhB decoloration could be significantly accelerated due to the high ionic strength. Increasing of the reaction temperature from 273 K to 333 K was beneficial to the RhB degradation, and the activation energy was determined to be 32.996 kJ/mol. Bleaching rate of RhB with the examined cations increased with the order of NH4+< Na+< K+< Al3+< Ca2+< Mg2+. Some major degradation products of RhB were identified by GC-MS. The present study may have active technical implications for the treatment of dyestuff wastewater in practice. © 2013 Springer-Verlag Berlin Heidelberg.

DOI 10.1007/s11356-013-1678-x
Citations Scopus - 25Web of Science - 20
2013 Guo YG, Huang P, Zhang WG, Yuan XW, Fan FX, Wang HL, et al., 'Leaching of heavy metals from Dexing copper mine tailings pond', Transactions of Nonferrous Metals Society of China (English Edition), 23 3068-3075 (2013)

The wastewater source of 4# tailing pond in Dexing copper mine consists of alkaline flotation pulp and acid mine drainage (AMD) from the nearby opencast mine. Therefore, the heavy... [more]

The wastewater source of 4# tailing pond in Dexing copper mine consists of alkaline flotation pulp and acid mine drainage (AMD) from the nearby opencast mine. Therefore, the heavy metals in tailing ore are very likely to be released due to acidification from AMD. The leaching behaviors of Zn, Cu, Fe and Mn in mine tailings from Dexing copper mine were investigated by a series of laboratory batch experiments. The effectcs of pH, temperature, particle size and contact time on the leachability of such heavy metals were examined. It was evident that Zn, Cu, Fe and Mn were major heavy metals in the tailings while gangue minerals like quartz were major constituents in examined tailings. The tailing dissolution reaction was controlled by the acid, whose kinetics could be expressed according to the heterogeneous reaction models and explained by a shrinking core model with the surface chemical reaction as the rate-controlling step. The leachability of all metals examined depended on pH and contact time. The batch studies indicated that the maximum leaching ratios of Zn, Cu, Fe and Mn at pH 2.0 were 5.4%, 5.8%, 11.1% and 34.1%, respectively. The dissolubility of all metals examined was positively correlated to the temperatures. The particle size would not change dissolution tendency of those heavy metals, but decrease the concentrations of leached heavy metals. © 2013 The Nonferrous Metals Society of China.

DOI 10.1016/S1003-6326(13)62835-6
Citations Scopus - 26
2013 Xu L, Yuan R, Guo Y, Xiao D, Cao Y, Wang Z, Liu J, 'Sulfate radical-induced degradation of 2,4,6-trichlorophenol: A de novo formation of chlorinated compounds', Chemical Engineering Journal, 217 169-173 (2013) [C1]

The degradation of 2,4,6-trichlorophenol (TCP) by sulfate radical generated via Co(II)-mediated activation of peroxymonosulfate (PMS) was examined. The influencing factors, such a... [more]

The degradation of 2,4,6-trichlorophenol (TCP) by sulfate radical generated via Co(II)-mediated activation of peroxymonosulfate (PMS) was examined. The influencing factors, such as substrate concentration and pH were investigated. The initial pH and its adjustment orders significantly affected the TCP degradation and mineralization. Several chlorinated products were detected, as well as some carboxylic acids, such as glycolic acid and oxalic acid. Many polychlorinated (chlorine atom number =3) aromatics (e.g. 2,4,5-trichlorophenol, 2,3,4,6-tetrachlorophenol, 2,3,5,6-tetrachloro-1,4-benzenediol) and even their ring-opening products (e.g. 2,4-dichloro-5-oxo-2-hexenedioic acid, 1,1,3,3-tetrachloro-2-propanone) were identified, indicating a de novo formation mechanism of organohalogens may be involved in TCP degradation. The released chlorine atoms from TCP and/or dichloride radicals activated by sulfate radicals played an important role. This finding may have significant scientific and technical implications for utilizing Co/PMS reagent to detoxify chlorinated pollutants. © 2012 Elsevier B.V.

DOI 10.1016/j.cej.2012.11.112
Citations Scopus - 47Web of Science - 43
2013 Guo Y-G, Huang P, Zhang W-G, Yuan X-W, Fan F-X, Wang H-L, et al., 'Leaching of heavy metals from Dexing copper mine tailings pond', TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA, 23 3068-3075 (2013)
DOI 10.1016/S1003-6326(1362835-6
Citations Web of Science - 21
2012 Ditte K, Jiang W, Schemme T, Denz C, Wang Z, 'Innovative sensitizer DiPBI outperforms PCBM', Advanced Materials, 24 2104-2108 (2012)

A new photorefractive (PR) material sensitized with a novel functional unit DiPBI is prepared based on the guest/host approach. This unique mixture exhibits strong absorption in t... [more]

A new photorefractive (PR) material sensitized with a novel functional unit DiPBI is prepared based on the guest/host approach. This unique mixture exhibits strong absorption in the whole range of visible light. Moreover, the photorefractive performance as well as PR speed is improved by far compared to the widely used sensitizer PCBM. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/adma.201104381
Citations Scopus - 15
2012 Lv A, Puniredd SR, Zhang J, Li Z, Zhu H, Jiang W, et al., 'High mobility, air stable, organic single crystal transistors of an n-type diperylene bisimide', Advanced Materials, 24 2626-2630 (2012)

A new n-type organic semiconductor, i.e., C12-4CldiPBI, is synthesized by a simple and facile route. Single crystal ribbons of C12-4CldiPBI are grown facilely by a solvent vapor d... [more]

A new n-type organic semiconductor, i.e., C12-4CldiPBI, is synthesized by a simple and facile route. Single crystal ribbons of C12-4CldiPBI are grown facilely by a solvent vapor diffusion strategy. Organic field-effect transistors based on individual ribbons are fabricated by a new technique named "Au stripe mask" method. All devices exhibit excellent n-type transistor behavior with negligible hysteresis, and all devices give an electron mobility over 1.0 cm 2 V -1 s -1 with the highest mobility of 4.65 cm 2 V -1 s -1. Moreover, the devices exhibit excellent air stability. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/adma.201104987
Citations Scopus - 140
2012 Jiang L, Dong H, Meng Q, Tan J, Jiang W, Xu C, et al., 'Molecular crystal lithography: A facile and low-cost approach to fabricate nanogap electrodes', Advanced Materials, 24 694-698 (2012)

A novel cost-efficient and facile technique, molecular crystal lithography, to fabricate nanogap electrodes efficiently is reported. The gap width of the electrodes can be tuned f... [more]

A novel cost-efficient and facile technique, molecular crystal lithography, to fabricate nanogap electrodes efficiently is reported. The gap width of the electrodes can be tuned from ~9 nm to several micrometers. Organic field-effect transistors based on the nanogap electrodes all exhibit a high performance, indicating the effectiveness and practicability of molecular crystal lithography for mass production of nanogap electrodes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/adma.201103098
Citations Scopus - 17
2012 Yue W, Lv A, Gao J, Jiang W, Hao L, Li C, et al., 'Hybrid rylene arrays via combination of stille coupling and C-H transformation as high-performance electron transport materials', Journal of the American Chemical Society, 134 5770-5773 (2012)

Hybrid rylene arrays have been prepared via a combination of Stille coupling and C-H transformation. The ability to extend the p system along the equatorial axis of rylenes not on... [more]

Hybrid rylene arrays have been prepared via a combination of Stille coupling and C-H transformation. The ability to extend the p system along the equatorial axis of rylenes not only leads to broadened light absorption but also increases the electron affinity, which can facilitate electron injection and transport with ambient stability. © 2012 American Chemical Society.

DOI 10.1021/ja301184r
Citations Scopus - 95
2012 Wang M, Li C, Lv A, Wang Z, Bo Z, 'Spirobifluorene-based conjugated polymers for polymer solar cells with high open-circuit voltage', Macromolecules, 45 3017-3022 (2012)

A new alternating copolymer (PSFDTBT) based on spirobifluorene, thiophene, and benzothiadiazole units has been synthesized. PSFDTBT has an optical band gap of 1.97 eV with the low... [more]

A new alternating copolymer (PSFDTBT) based on spirobifluorene, thiophene, and benzothiadiazole units has been synthesized. PSFDTBT has an optical band gap of 1.97 eV with the low-lying HOMO energy level at -5.4 eV. The hole mobility of the pristine PSFDTBT film spin-cast from o-dichlorobenzene (DCB) solution is 7.26 × 10-3cm2V-1s-1with on/off ratios in the order of 105. Polymer solar cell devices based on the blend films of PSFDTBT and PC71BM show a high open-circuit voltage of 0.94 V and a power conversion efficiency of 4.6% without any post-treatment. All the device measurements were performed in air without encapsulation. This is the first report on spirobifluorene-based conjugated polymers used for polymer solar cells, demonstrating the great potential of spirobifluorene moiety as an electron-donating unit for the construction of main chain donor-acceptor alternating conjugated polymers for high performance polymer solar cells. © 2012 American Chemical Society.

DOI 10.1021/ma202752h
Citations Scopus - 28
2012 Wang M, Li C, Lv A, Wang Z, Bo Z, Zhang F, 'Synthesis and photovoltaic behaviors of benzothiadiazole- and triphenylamine-based alternating copolymers', Polymer, 53 324-332 (2012)

A series of donor-acceptor (D-A) alternating copolymers (P1, P2 and P3) with thiophene-benzothiadiazole-thiophene-triphenylamine main chain have been synthesized by Suzuki polycon... [more]

A series of donor-acceptor (D-A) alternating copolymers (P1, P2 and P3) with thiophene-benzothiadiazole-thiophene-triphenylamine main chain have been synthesized by Suzuki polycondensation. P1, P2, and P3 possess medium optical band gaps of 1.99, 1.97 and 1.93 eV, respectively. Bulk heterojunction polymer solar cells (BHJ PSCs) with these polymers as donor and PC71BM as acceptor showed power conversion efficiency (PCE) in the range of 2.1-2.8%. The highest PCE of 2.8 % was achieved for P1 with short circuit current (Jsc) of 7.8 mA/cm2. This study offers a useful and important insight for designing triphenylamine derivative-based polymers used for efficient PSCs. © 2011 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.polymer.2011.12.026
Citations Scopus - 18
2012 Hao L, Jiang W, Wang Z, 'Integration of nitrogen into coronene bisimides', Tetrahedron, 68 9234-9239 (2012)

N-Decorated PBIs and CBIs have been synthesized by the combination of Pictet-Spengler condensation and subsequent oxidative aromatization based on highly electron-deficient amino-... [more]

N-Decorated PBIs and CBIs have been synthesized by the combination of Pictet-Spengler condensation and subsequent oxidative aromatization based on highly electron-deficient amino-PBIs. A detailed analysis of their photophysical properties and molecular crystals has shown that the lateral aryl groups appended on the N-heterocycle have a negligible effect on their optical absorptions and electrochemical potentials, but the subtle modification leads to significant variations on arrangement in the solid state. © 2012 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.tet.2012.08.084
Citations Scopus - 10
2012 Cui Y, Yao D, Chen Y, Wang Z, 'Synthesis and properties of novel functional polymers from tetrachlorinated perylene bisimide', Journal of Polymer Science, Part A: Polymer Chemistry, 50 3485-3492 (2012)

Asymmetric tetrachlorinated perylene-3,4,9,10-tetracarboxylic acid bisimides (4Cl-PBI) were prepared in one-pot by a reaction of tetrachlorinated perylene-3,4,9,10-tetracarboxylic... [more]

Asymmetric tetrachlorinated perylene-3,4,9,10-tetracarboxylic acid bisimides (4Cl-PBI) were prepared in one-pot by a reaction of tetrachlorinated perylene-3,4,9,10-tetracarboxylic acid dianhydride with a mixture of 2-aminoethanol and dodecanamine or 2-decyltetradecan-1-amine. Then, two 4Cl-PBI methacrylates bearing one (M1) and two (M2) long alkyl tails were prepared, and a series of functional homopolymers were obtained by subjecting conventional radical polymerization and atom transfer radical polymerization. Furthermore, amphiphilic block copolymers pendent with 4Cl-PBI units, PEO-PM1 and PEO-PM2, were prepared using monomethoxyl PEO bromoisobutyrate as a macroinitiator. Size exclusion chromatography, UV-vis spectroscopy, fluorescence spectroscopy, and cyclic voltammetry have been applied to characterize the polymers obtained. Moreover, the Ullmann reactions between the grafted 4Cl-PBI units were conducted to form large p units, and the PEO-PM2 block copolymers gave di- or tri-PBI units in about 30%. Also, self-assembly of the amphiphilic block copolymers PEO-PM1 and PEO-PM2 in water was applied to generate spherical nanoparticles of 4Cl-PBI. Copyright © 2012 Wiley Periodicals, Inc.

DOI 10.1002/pola.26154
Citations Scopus - 3
2012 Jiang W, Xiao C, Hao L, Wang Z, Ceymann H, Lambert C, et al., 'Localization/delocalization of charges in bay-linked perylene bisimides', Chemistry - A European Journal, 18 6764-6775 (2012)

The copper-mediated Ullmann coupling of 1,7-dibromoperylene bisimides afforded structurally perfect singly-linked perylene bisimide (PBI) arrays, whilst the homo-coupling of 1,12-... [more]

The copper-mediated Ullmann coupling of 1,7-dibromoperylene bisimides afforded structurally perfect singly-linked perylene bisimide (PBI) arrays, whilst the homo-coupling of 1,12-dibromoperylene bisimides gave doubly-linked and triply-linked diperylene bisimides. The interactions of three bay-linked diperylene bisimides that differed in their linkage (singly, doubly, and triply) were investigated in their neutral and reduced forms (mono-anion to tetra-anion). UV/Vis absorption and fluorescence spectroscopy revealed different degrees of interaction, which was explained by exciton coupling and conjugation effects. The electrochemical properties and spectroelectrochemistry also showed quite-different degrees of PBI interactions in the reduced mixed-valence species, which was apparent by the observation of CT bands. The interpretation of the experimental findings was supported by spin-restricted and -unrestricted DFT and time-dependent TD-DFT calculations with the long-range-corrected CAM-B3LYP functional. Accordingly, the degree of interaction in both the neutral and reduced forms of the bay-linked PBIs was qualitatively in the order doubly linked<singly linked-triply linked, owing to the different degrees of twisting and flexibility between the two PBIs moieties. Only triply linked diPBI showed completely delocalized wavefunctions over the entire p-system. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/chem.201103954
Citations Scopus - 42
2012 Sun Y, Li Z, Wang Z, 'Self-assembled monolayer and multilayer films based on l-lysine functionalized perylene bisimide', Journal of Materials Chemistry, 22 4312-4318 (2012)

l-Lysine functionalized tetrachloroperylene bisimide (Lys-4ClPBI-Lys) was synthesized, and its aqueous self-assembly behaviours were investigated at different pH values. The zwitt... [more]

l-Lysine functionalized tetrachloroperylene bisimide (Lys-4ClPBI-Lys) was synthesized, and its aqueous self-assembly behaviours were investigated at different pH values. The zwitterionic-type Lys-4ClPBI-Lys amphiphile spontaneously self-assembled into a uniform monolayer film in water at pH ranging from 9 to 1, whereas it did not formed any ordered aggregates in solution with pH above 10. Formation of the monolayer film was believed due to synergistic interaction of directional p-p interactions and intermolecular hydrogen bonding. In contrast, the addition of copper(ii) ions induced the formation of multilayer films due to inter-film ligation between Cu 2+ and the a-amino acid moiety. The corresponding self-assembly behaviours and assemblies' structures were characterized using UV-vis absorption and fluorescence emission spectroscopy, cryogenic transmission electron microscopy, atomic force microscopy, and X-ray diffraction. © 2012 The Royal Society of Chemistry.

DOI 10.1039/c1jm14521e
Citations Scopus - 22
2012 Deng J, Wang B, Shi Y, Song Q, Wang A, Hao L, et al., 'Poly (zinc phthalocyanine) nanoribbons and their application in the high-sensitive detection of lead ions', Macromolecular Chemistry and Physics, 213 1051-1059 (2012)

Novel poly (zinc phthalocyanine) (poly(ZnPc)) nanoribbons have been obtained by polycyclotetramerization of bifunctional ZnPc monomers. The microstructures of poly(ZnPc) nanoribbo... [more]

Novel poly (zinc phthalocyanine) (poly(ZnPc)) nanoribbons have been obtained by polycyclotetramerization of bifunctional ZnPc monomers. The microstructures of poly(ZnPc) nanoribbons are characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermalgravimetry. Due to its unique two-dimensional structure and rich functionality, the poly(ZnPc) nanoribbons exhibit excellent sensitivity in detecting lead ions (Pb 2+) by using anodic stripping voltammetry (ASV) method, and the detection limit for Pb 2+ is 10 -10 mol L -1 in aqueous media, which is much attractive for the development of portable and highly sensitive heavy metal ion sensors. Full Paper: As a typical two-dimensional aromatic nanomaterial, poly (zinc phthalocyanine) nanoribbons are synthesized via polycyclotetramerization of bifunctional zinc phthalocyanine monomers. The material is characterized in detail and excellent sensitivity in detecting lead ions is demonstrated. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/macp.201100613
Citations Scopus - 7
2012 Lv A, Li Y, Yue W, Jiang L, Dong H, Zhao G, et al., 'High performance n-type single crystalline transistors of naphthalene bis(dicarboximide) and their anisotropic transport in crystals', Chemical Communications, 48 5154-5156 (2012)

High-performance n-type organic single crystal transistors of a naphthalene diimide are demonstrated. The accomplished transistors exhibit electron mobility as high as 0.7 cm 2 V ... [more]

High-performance n-type organic single crystal transistors of a naphthalene diimide are demonstrated. The accomplished transistors exhibit electron mobility as high as 0.7 cm 2 V -1 s -1. The anisotropic charge transport in the elongated hexagonal crystals of the naphthalene diimide is also explored. The transport anisotropy along different directions is at least 1.6 (mobility ratio). © 2012 The Royal Society of Chemistry.

DOI 10.1039/c2cc31619f
Citations Scopus - 26
2012 Li Y, Xu W, Motta SD, Negri F, Zhu D, Wang Z, 'Core-extended rylene dyes via thiophene annulation', Chemical Communications, 48 8204-8206 (2012)

Annulation of thiophenes directly into the bay regions of rylene dyes through effective Stille coupling and subsequent ring-fusion under Scholl conditions leads to core-extended r... [more]

Annulation of thiophenes directly into the bay regions of rylene dyes through effective Stille coupling and subsequent ring-fusion under Scholl conditions leads to core-extended rylene tetracarboxylic diimides with interesting electro-optical properties. © 2012 The Royal Society of Chemistry.

DOI 10.1039/c2cc33529h
Citations Scopus - 18
2012 Li Y, Wang C, Li C, Di Motta S, Negri F, Wang Z, 'Synthesis and properties of ethylene-annulated Di(perylene diimides)', Organic Letters, 14 5278-5281 (2012)

A new synthetic method toward ethylene-annulated di(perylene diimides) from easily available ethylene-annulated di(perylene esters), which is conducted by ICl-induced cyclization ... [more]

A new synthetic method toward ethylene-annulated di(perylene diimides) from easily available ethylene-annulated di(perylene esters), which is conducted by ICl-induced cyclization and Mizoroki-Heck coupling of ethynylene-linked di(perylene esters), is reported. © 2012 American Chemical Society.

DOI 10.1021/ol302434y
Citations Scopus - 19
2012 Liu J, Ditte K, Jiang W, Wang Z, Denz C, 'Dipolar-modulated charge-doped trilayer organic semiconductor n-n heterojunction', Small, 8 546-551 (2012)

A novel dipolar-modulated charge-doped trilayer n-n organic heterojunction with a bidirectional tunable energy band discontinuity is constructed. The rectifying mechanism of the t... [more]

A novel dipolar-modulated charge-doped trilayer n-n organic heterojunction with a bidirectional tunable energy band discontinuity is constructed. The rectifying mechanism of the trilayer is similar to the rectifying and inverse-rectifying characteristics from n-p and p-n junctions, respectively. Zero-bias optoelectronic behavior and persistent photoconductivity are discovered. These results show that what are viewed as technological hurdles in the development of an organic n-n heterojunction should, in fact, lead to a better approach in organic optoelectronics. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/smll.201101776
2012 Schemme T, Travkin E, Ditte K, Jiang W, Wang Z, Denz C, 'TPD doped polystyrene as charge transporter in DiPBI sensitized photorefractive composites', Optical Materials Express, 2 856-863 (2012)

We incorporate a mixture of polystyrene (PS) and the highly conductive N, N&apos;-diphenyl-N, N&apos;-bis(3-methylphenyl)-[1,1&apos;-biphenyl]-4,4&apos;-diamine (TPD) as charge tr... [more]

We incorporate a mixture of polystyrene (PS) and the highly conductive N, N'-diphenyl-N, N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine (TPD) as charge transporting agent into a photorefractive composite, wherein the liquid crystal 4-cyano-4-n-pentylbiphenyl (5CB) is the electro-optical unit and the perylene bisimide dimer DiPBI acts as sensitizing component. Investigation of the photocurrent reveals a strong enhancement of the photoconductivity. Compared to composites, wherein poly-n-vinylcarbazole (PVK) is the charge transporting agent, the internal photocurrent efficiency is enhanced 11 times. This dramatic improvement is attributed to an increase of charge generation and transport and it allows for a reduction of the applied electric field to get a photoconductivity that is comparable to PVK comprising composites. © 2012 Optical Society of America.

DOI 10.1364/OME.2.000856
Citations Scopus - 3
2012 Guo Y, Lou X, Xiao D, Xu L, Wang Z, Liu J, 'Sequential reduction-oxidation for photocatalytic degradation of tetrabromobisphenol A: Kinetics and intermediates', Journal of Hazardous Materials, 241-242 301-306 (2012) [C1]

CBr bond cleavage is considered as a key step to reduce their toxicities and increase degradation rates for most brominated organic pollutants. Here a sequential reduction/oxidati... [more]

CBr bond cleavage is considered as a key step to reduce their toxicities and increase degradation rates for most brominated organic pollutants. Here a sequential reduction/oxidation strategy (i.e. debromination followed by photocatalytic oxidation) for photocatalytic degradation of tetrabromobisphenol A (TBBPA), one of the most frequently used brominated flame retardants, was proposed on the basis of kinetic analysis and intermediates identification. The results demonstrated that the rates of debromination and even photodegradation of TBBPA strongly depended on the atmospheres, initial TBBPA concentrations, pH of the reaction solution, hydrogen donors, and electron acceptors. These kinetic data and byproducts identification obtained by GC-MS measurement indicated that reductive debromination reaction by photo-induced electrons dominated under N2-saturated condition, while oxidation reaction by photoexcited holes or hydroxyl radicals played a leading role when air was saturated. It also suggested that the reaction might be further optimized for pretreatment of TBBPA-contaminated wastewater by a two-stage reductive debromination/subsequent oxidative decomposition process in the UV-TiO2 system by changing the reaction atmospheres. © 2012 Elsevier B.V.

DOI 10.1016/j.jhazmat.2012.09.044
Citations Scopus - 29Web of Science - 26
2012 Wang ZH, Xie XH, Liu JS, 'Experimental measurements of short-term adsorption of Acidithiobacillus ferrooxidans onto chalcopyrite', Transactions of Nonferrous Metals Society of China (English Edition), 22 442-446 (2012)

The influencing factors in adsorption such as adsorption time, pulp concentration, bacterial concentration, pH as well as ionic strength were investigated to explore the relations... [more]

The influencing factors in adsorption such as adsorption time, pulp concentration, bacterial concentration, pH as well as ionic strength were investigated to explore the relationship among them and bacterial adsorption. The adsorption was a rapid process for bacterial adhesion to chalcopyrite. The extent of adsorption increased with increasing initial bacterial concentration and pulp concentration. The optimal pH for Acidithiobacillus ferrooxidans adsorption onto chalcopyrite surfaces was in the range of pH 1-3. The increase of ionic strength led to decrease in bacterial adsorption, which can be well explained by electric double layer theory. The adsorption behavior appeared to be controlled by both hydrophobic and electrostatic interactions at the interface of bacteria and mineral. © 2012 The Nonferrous Metals Society of China.

DOI 10.1016/S1003-6326(11)61196-5
Citations Scopus - 9Web of Science - 7
2012 Wang Z, Song W, Ma W, Zhao J, 'Environmental photochemistry of iron complexes and their involvement in environmental chemical processes', Progress in Chemistry, 24 423-432 (2012)

Iron is one of the most abundant metals in the continental crust, while most of dissolved iron is complexed with organic ligands. The irradiated iron complexes in the environment ... [more]

Iron is one of the most abundant metals in the continental crust, while most of dissolved iron is complexed with organic ligands. The irradiated iron complexes in the environment undergo direct photolysis and secondary (photo)chemical reactions, generating Fe(II), organic radicals and some reactive oxygen species (ROS). Environmental photochemistry of iron complexes can greatly affect ROS dynamics, organics degradation and redox cycling of other elements. Therefore, it is becoming a hot topic in the international field of environmental sciences research. This review firstly summarizes three types of iron complexes including inorganic Fe complexes, simple organic Fe complexes and macrocyclic organic Fe complexes, and photoreduction mechanisms of iron complexes. Secondly, the potential oxidants of Fe(II) in acidic aquatic environment are introduced. The oxidation kinetics, possible reaction mechanism and influencing factors (such as dissolved oxygen concentration, pH, ionic strength, temperature and natural organic matters concentrations) of (photo)chemical oxidation of Fe(II) are elucidated. This review also highlights recent findings in the study of environmental processes involving iron photochemistry. Finally, the future prospects in this field are discussed based on the current status.

Citations Scopus - 6
2012 Yuan R, Ramjaun SN, Wang Z, Liu J, 'Photocatalytic degradation and chlorination of azo dye in saline wastewater: Kinetics and AOX formation', Chemical Engineering Journal, 192 171-178 (2012) [C1]

Chloride ion as one of the major salt components in dyestuff wastewaters can greatly affect the homogenous OH radical-based advanced oxidation processes (AOPs), but little informa... [more]

Chloride ion as one of the major salt components in dyestuff wastewaters can greatly affect the homogenous OH radical-based advanced oxidation processes (AOPs), but little information is available now for heterogeneous AOPs like UV/TiO2 under similar conditions. Here the effects of chloride on kinetics and reaction intermediates of dye degradation in heterogeneous photocatalysis were examined. The dye degradation efficiency in UV/TiO2 process was investigated as a function of a wide range of salinity and pH. The chloride ion was found to have a dual effect on both the dye decoloration and mineralization in UV/TiO2 system due to different mechanisms involved. Higher Cl- concentration would inhibit dye degradation, especially in acidic medium. AOX (halogenated organic compounds adsorbable on activated carbon) generated increased with the increasing content of chloride ion present in the solution. Several toxic chlorinated byproducts were firstly identified during the dye degradation in UV/TiO2 process using GC-MS method and possible decomposition pathways were proposed. These findings may have significant technical implications for optimizing the photochemical technologies in salt-rich wastewater treatment. © 2012 Elsevier B.V.

DOI 10.1016/j.cej.2012.03.080
Citations Scopus - 63Web of Science - 64
2012 Yuan R, Ramjaun SN, Wang Z, Liu J, 'Concentration profiles of chlorine radicals and their significances in

In order to further understand the mechanism details during saline wastewater treatment by¿OH-based advanced oxidation processes (AOPs), the degradation efficiency of an azo dye A... [more]

In order to further understand the mechanism details during saline wastewater treatment by¿OH-based advanced oxidation processes (AOPs), the degradation efficiency of an azo dye Acid Orange 7 (AO7) in UV/H2O2process was investigated as a function of a wide range of salinity and pH. Kinetic modeling results demonstrated that the inhibitory effect of Cl-on AO7 degradation observed in the laboratory experiments could be attributed to both scavenging effect of Cl-on¿OH and the much lower reactivity of chlorine radicals formed, although the chlorine radicals may be more abundant than¿OH. Such retardation behavior was favored under acidic conditions due to a lower yield of¿OH generated by the dissociation of ClOH¿-to¿OH and Cl-. Traces of Br-had a greater inhibitory effect on AO7 bleaching rate than Cl-. AOX (halogenated organic compounds adsorbable on activated carbon) was found to increase with the increasing content of Cl-. Based on the intermediate products and especially several toxic halogenated byproducts identified by GC-MS, the possible degradation pathways of saline dyeing wastewater were proposed. © 2012 Elsevier B.V.

DOI 10.1016/j.cej.2012.07.127
Citations Scopus - 24Web of Science - 21
2012 Wang Z, Chen C, Ma W, Zhao J, 'Photochemical coupling of iron redox reactions and transformation of low-molecular-weight organic matter', Journal of Physical Chemistry Letters, 3 2044-2051 (2012)

The photoreactions between Fe(III)/Fe(II) and low-molecular-weight organic matter (LMWOM) under solar irradiation have significant implications for many biogeochemical cycles on t... [more]

The photoreactions between Fe(III)/Fe(II) and low-molecular-weight organic matter (LMWOM) under solar irradiation have significant implications for many biogeochemical cycles on the Earth and for the fates of environmental pollutants. In this Perspective, we focus on several fundamental aspects of the photochemical processes that couple the redox cycling of iron species and transformation of organic substrates. The primary photoprocesses (e.g., intramolecular electron transfer or photodissociation) are first highlighted by introducing the recently disputed observations on the photolysis of ferrioxalate complexes. The effects of LMWOM and its daughter radicals on the photochemical redox cycling of iron species are discussed with special attention given to the example of Fe-malonate complexes. These processes and mechanisms would provide us some refreshed understanding of environmental photochemistry of LMWOM and the iron species and would be helpful for our assessment of photochemical decontamination of organic pollutants. © 2012 American Chemical Society.

DOI 10.1021/jz3005333
Citations Scopus - 20Web of Science - 17
2012 Wang Z, Song W, Ma W, Zhao J, 'Environmental Photochemistry of Iron Complexes and Their Involvement in Environmental Chemical Processes', PROGRESS IN CHEMISTRY, 24 423-432 (2012)
Citations Web of Science - 6
2011 Peng Q, Niu Y, Wang Z, Jiang Y, Li Y, Liu Y, Shuai Z, 'Theoretical predictions of red and near-infrared strongly emitting X-annulated rylenes', Journal of Chemical Physics, 134 (2011)

The optical properties of rylenes are extremely interesting because their emission colors can be tuned from blue to near-infrared by simply elongating the chain length. However, f... [more]

The optical properties of rylenes are extremely interesting because their emission colors can be tuned from blue to near-infrared by simply elongating the chain length. However, for conjugated chains, the dipole-allowed odd-parity 1Buexcited state often lies above the dipole-forbidden even-parity 2Agstate as the chain length increases, thus preventing any significant luminescence according to Kashas rule. We systemically investigated the 1Bu2Agcrossover behaviors with respect to the elongating rylene chain length with various quantum chemistry approaches, such as time-depended density functional theory (TDDFT), complete active space self-consistent field theory (CASSCFCASPT2), multireference configuration interaction (MRCI)Zerners intermediate neglect of diatomic overlap (ZINDO), and MRCImodified neglect of differential overlap. The calculated results by CASSCFCASPT2 and MRCIZINDO are completely coherent: the optical active 1Bustate lies below the dark B3gor 2Agstate for perylene and terrylene, which results in strong fluorescence; while a crossover to S1= 2Agoccurs and leads to much weaker fluorescence for quaterrylene. Then we put forward a molecular design rule on how to recover fluorescence for the longer rylenes by introducing heteroatom bridges. Several heteroatom-annulated rylenes are designed theoretically, which are predicted to be strongly emissive in the red and near-infrared ranges. These are further confirmed by theoretical emission spectra as well as radiative and nonradiative decay rate calculations by using the vibration correlation function formalisms we developed earlier coupled with TDDFT. © 2011 American Institute of Physics.

DOI 10.1063/1.3549143
Citations Scopus - 13
2011 Sun Y, He C, Sun K, Li Y, Dong H, Wang Z, Li Z, 'Fine-tuned nanostructures assembled from l-lysine-functionalized perylene bisimides', Langmuir, 27 11364-11371 (2011)

Controllable nanostructures with tunable dimensions were obtained via self-assembly of CBZ-l-lysine-functionalized tetrachloroperylene bisimides (4ClPBI-Lys). Depending on the nat... [more]

Controllable nanostructures with tunable dimensions were obtained via self-assembly of CBZ-l-lysine-functionalized tetrachloroperylene bisimides (4ClPBI-Lys). Depending on the nature of substitute, solvent polarity, and sample concentration, 4ClPBI-Lys could form nanosphere, nanowire, nanobelt, and nanosheet, which were found to have different degree of molecular ordering. The effects of substitution position with respect to l-lysine on 4ClPBI were also explored in terms of assembly nanostructures. Hydrogen bonding was important to promote formation of long-range ordering. The nanostructures of different assemblies were characterized using SEM, TEM, XRD, UV-vis, and FTIR spectroscopy. For each obtained supramolecular assembly, we also found that the molecular packing motif ultimately determined the corresponding devices' electronic properties. © 2011 American Chemical Society.

DOI 10.1021/la202107r
Citations Scopus - 62
2011 Chen C, Wang Z, Li Z, 'Thermoresponsive polypeptides from pegylated poly-l-glutamates', Biomacromolecules, 12 2859-2863 (2011)

The synthesis and characterization of new thermoresponsive pegylated poly-l-glutamate (poly-l-EG xGlu) are described. The obtained polypeptides display low critical solution tempe... [more]

The synthesis and characterization of new thermoresponsive pegylated poly-l-glutamate (poly-l-EG xGlu) are described. The obtained polypeptides display low critical solution temperature (LCST) behaviors in water, and the LCST can be tuned via copolymerization of different amino acid monomers at varied molar ratio. This is the first example of thermoresponsive polypeptide made from ring-opening polymerization of a-amino acid N-carboxyanhydrides (NCAs). Circular dichroism characterizations reveal that the secondary structure of poly-l-EG xGlu depended on the chain length of the side chain. © 2011 American Chemical Society.

DOI 10.1021/bm200849m
Citations Scopus - 152
2011 Jiang W, Zhou Y, Geng H, Jiang S, Yan S, Hu W, et al., 'Solution-processed, high-performance nanoribbon transistors based on dithioperylene', Journal of the American Chemical Society, 133 1-3 (2011)

Solution-processed, high-performance 1D single-crystalline nanoribbon transistors fabricated from dithioperylene are described. The integration of two sulfur atoms into the peryle... [more]

Solution-processed, high-performance 1D single-crystalline nanoribbon transistors fabricated from dithioperylene are described. The integration of two sulfur atoms into the perylene skeleton induces a compressed highly ordered packing mode directed by ¿S interactions. The mobilities of up to 2.13 cm2 V-1 s-1 for a dithioperylene individual nanoribbon make it particularly attractive for electronic applications. © 2010 American Chemical Society.

DOI 10.1021/ja107599r
Citations Scopus - 86
2011 Yue W, Gao J, Li Y, Jiang W, Di Motta S, Negri F, Wang Z, 'One-pot synthesis of stable NIR tetracene diimides via double cross-coupling', Journal of the American Chemical Society, 133 18054-18057 (2011)

Tetracene tetracarboxylic diimides have been synthesized based on direct double ring extension of electron-deficient naphthalene diimides involving metallacyclopentadienes. Atomic... [more]

Tetracene tetracarboxylic diimides have been synthesized based on direct double ring extension of electron-deficient naphthalene diimides involving metallacyclopentadienes. Atomic structure and electronic transitions responsible for their NIR absorption spectra are investigated with quantum-chemical calculations. In light of their unique structure and admirable photophysical and electronic properties, this new molecular skeleton is promising candidate for n-type semiconductors. © 2011 American Chemical Society.

DOI 10.1021/ja207630a
Citations Scopus - 56
2011 Li Y, Hao L, Fu H, Pisula W, Feng X, Wang Z, 'Columnar liquid crystalline bis-N-annulated quaterrylenes', Chemical Communications, 47 10088-10090 (2011)

Columnar liquid crystalline bis-N-annulated quaterrylenes have been prepared from readily available N-annulated perylenes by DDQ/Sc(OTf)3 oxidative coupling and ring-fusion. © The... [more]

Columnar liquid crystalline bis-N-annulated quaterrylenes have been prepared from readily available N-annulated perylenes by DDQ/Sc(OTf)3 oxidative coupling and ring-fusion. © The Royal Society of Chemistry 2011.

DOI 10.1039/c1cc13398e
Citations Scopus - 20
2011 Ramjaun SN, Yuan R, Wang Z, Liu J, 'Degradation of reactive dyes by contact glow discharge electrolysis in the presence of Cl

The plasma generated around the anode during contact glow discharge electrolysis (CGDE) is a rich source of hydroxyl (OH) radicals that can efficiently degrade organic contaminant... [more]

The plasma generated around the anode during contact glow discharge electrolysis (CGDE) is a rich source of hydroxyl (OH) radicals that can efficiently degrade organic contaminants in aqueous solutions. The degradation of textile azo dyestuffs, Reactive Yellow 176 (Y3RS), Reactive Red 239 (R3BS) and Reactive Black 5 (B5), by anodic CGDE was investigated in the presence of chloride (Cl-) ions. The degradation kinetics of the dyes was dependent on the concentration of Cl- ions and on the respective dye being treated. R3BS degradation was inhibited by Cl- ions in the range of 0-0.01 M. When the Cl- ion concentration was less than 0.02 M, the dyes followed pseudo first-order degradation kinetics. For concentrations greater than 0.02 M, the degradation of Y3RS and B5 was significantly enhanced compared to the degradation of R3BS and deviated from first-order reaction kinetics. The presence of Cl- ions (0.03 M) did not appear to improve dye mineralization but resulted in the formation of adsorbable organic halogens (AOX). The results indicated that the AOX could be abated with prolonged electrolytic treatment. This observation is significant for the assessment of the environmental impact of this technology for wastewater treatment. © 2011 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.electacta.2011.09.052
Citations Scopus - 20Web of Science - 19
2011 Wang Z, Yuan R, Guo Y, Xu L, Liu J, 'Effects of chloride ions on bleaching of azo dyes by Co2+/oxone regent: Kinetic analysis', Journal of Hazardous Materials, 190 1083-1087 (2011) [C1]

Orange II (Org II), one of the most common used azo dyes, was taken as a model to investigate the effects of chloride ion on dye decoloration in cobalt/peroxymonosulfate (Co/PMS) ... [more]

Orange II (Org II), one of the most common used azo dyes, was taken as a model to investigate the effects of chloride ion on dye decoloration in cobalt/peroxymonosulfate (Co/PMS) system. A significant decrease in the rate of Org II decoloration was observed upon addition of Cl-(0.05-10mM), but further addition of Cl-(>50mM) apparently accelerated dyes degradation. This dual effect of chloride on dyes bleaching was also observed as other halide ions (e.g. Br-, I-) or other azo dyes were present in Co/PMS system. In the Co-free PMS solutions, the observed first-order rate constant always exponentially increased with the chloride content. The reactive chlorine species generated from chloride oxidation by PMS should be responsible for this non-radical mechanism for dye decoloration, however, these rapid decoloration of Org II as chloride ion was present, did not readily lead to much mineralization. Therefore, this finding may have significant technical implications for utilizing Co/PMS regent to detoxify chloride-rich azo dyes wastewater. © 2011 Elsevier B.V.

DOI 10.1016/j.jhazmat.2011.04.016
Citations Scopus - 120Web of Science - 112
2011 Yuan R, Ramjaun SN, Wang Z, Liu J, 'Effects of chloride ion on degradation of Acid Orange 7 by sulfate radical-based advanced oxidation process: Implications for formation of chlorinated aromatic compounds', Journal of Hazardous Materials, 196 173-179 (2011) [C1]

Sodium chloride is a common salt used during textile wet processes. Here a dual effect of chloride (i.e. inhibitory and accelerating effect) on azo dye (Acid Orange 7, AO7) degrad... [more]

Sodium chloride is a common salt used during textile wet processes. Here a dual effect of chloride (i.e. inhibitory and accelerating effect) on azo dye (Acid Orange 7, AO7) degradation in an emerging cobalt/peroxymonosulfate (Co/PMS) advanced oxidation process (AOP) was reported. Compared to OH-based AOPs, high concentrations of chloride (>5mM) can significantly enhance dye decoloration independent of the presence of the Co 2+ catalyst, but did greatly inhibit dye mineralization to an extent which was closely dependent upon the chloride content. Both UV-vis absorbance spectra and AOX determination indicated the formation of some refractory byproducts. Some chlorinated aromatic compounds, including 3-chloroisocoumain, 2-chloro-7-hydroxynaphthalene, 1,3,5-trichloro-2-nitrobenzene and tetrachlorohydroquione, were identified by GC-MS measurement in both Co/PMS/Cl - and PMS/Cl - reaction systems. Based on those experimental results, two possible branched (SO 4- radical-based and non-radical) reaction pathways are proposed. This is one of the very few studies dealing with chlorinated organic intermediates formed via chlorine radical/active chlorine species (HOCl/Cl 2) attack on dye compounds. Therefore, this finding may have significant technical implications for utilizing Co/PMS regent to detoxify chloride-rich azo dyes wastewater. © 2011 Elsevier B.V.

DOI 10.1016/j.jhazmat.2011.09.007
Citations Scopus - 207Web of Science - 187
2011 Wang ZH, Xie XH, Liu JS, 'Numerical modeling of potential profiles in electrical double layer of Acidithiobacillus ferrooxidans cell surface', Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals, 21 1485-1490 (2011)

The surface charge density, space charge density, surface potential (f0) and Donnan potential (fDon) on the surface of Acidithiobacillus ferrooxidans cultivated with elemental sul... [more]

The surface charge density, space charge density, surface potential (f0) and Donnan potential (fDon) on the surface of Acidithiobacillus ferrooxidans cultivated with elemental sulfur (S-A.ferrooxidans) were calculated by numerical simulation using the ion-impenetrable and ion-penetrable models. Zeta potential measurement show that the isoelectric point (IEP) of S-A.ferrooxidans is higher than that of bacterium cultured with Fe2+. It is concluded from fitting data by ionizable surface group model that S-A.ferrooxidans surface probably consists of much proteins, the ionization of amino group of which causes higher IEP (> 2). The ion-penetrable model reveals that f0 and fDon decrease rapidly at pH < 5 but hardly change when pH is 6-7. The thickness of electrical double layer of S-A.ferrooxidans is estimated as 5 nm. The electrical double layer of bacterial cell surface may have significant implications for ions transfer and nutrient transport, but their interaction is unfavorable for bacterial aggration.

Citations Scopus - 1
2011 Wang Z, Ma W, Chen C, Ji H, Zhao J, 'Probing paramagnetic species in titania-based heterogeneous photocatalysis by electron spin resonance (ESR) spectroscopy-A mini review', Chemical Engineering Journal, 170 353-362 (2011)

Many paramagnetic species such as active surface sites, reactive oxygen species (ROS) and organic radicals derived from the photodegradation of organics were involved in the heter... [more]

Many paramagnetic species such as active surface sites, reactive oxygen species (ROS) and organic radicals derived from the photodegradation of organics were involved in the heterogeneous photocatalysis. Identification and characterization of these paramagnetic species are essentially conducted using electron spin resonance (ESR) techniques, which can provide a detailed understanding of the radical composition and structure on the basis of the unique feature of g, hyperfine, and superhyperfine tensors for each kind of radicals of interest. In the present review, the basic theoretical principles of the ESR technique and its application in the field of TiO2-based heterogeneous photocatalysis are generally summarized. Two experimental approaches typical of ESR-direct monitoring of paramagnetic species or sites and spin-trapping technique have been described with particular attention to the choices of spin traps. The general features of the ESR spectra of photoinduced charges, inorganic and organic radicals in photocatalytic events are presented and discussed. In addition, some remarks will be made about the use of ESR in revealing the origin of enhanced photocatalytic activities in the mixed phase titania (P25) and visible-light-response N-doped TiO2. © 2010 Elsevier B.V.

DOI 10.1016/j.cej.2010.12.002
Citations Scopus - 131Web of Science - 118
2011 Chen X, Ma W, Li J, Wang Z, Chen C, Ji H, Zhao J, 'Photocatalytic Oxidation of Organic Pollutants Catalyzed by an Iron Complex at Biocompatible pH Values: Using O-2 as Main Oxidant in a Fenton-like Reaction', JOURNAL OF PHYSICAL CHEMISTRY C, 115 4089-4095 (2011) [C1]
DOI 10.1021/jp110277k
Citations Scopus - 29Web of Science - 28
2010 Li Y, Gao J, Di Motta S, Negri F, Wang Z, 'Tri-N-annulated hexarylene: An approach to well-defined graphene nanoribbons with large dipoles', Journal of the American Chemical Society, 132 4208-4213 (2010)

We report a highly efficient synthetic methodology toward tri-N-annulated hexarylenes from easily available N-annulated perylenes, which Is favored by the oxidative ring fusion dr... [more]

We report a highly efficient synthetic methodology toward tri-N-annulated hexarylenes from easily available N-annulated perylenes, which Is favored by the oxidative ring fusion driven by DDQ/Sc(OTf)3. To assist the characterization of the new compounds, quantum-chemical calculations of structural and spectroscopic properties have been carried out for three oligomers of N-annulated rylenes, It Is shown that tri-N-annulated hexarylene dyes display remarkably large dipole moments likely associated with the formation of H aggregates, as suggested by the marked concentration dependence of the measured UV-vis spectra. It is suggested that the combination of p-p stacking Interactions and dipole-dipole interactions may favor the formation of highly ordered supramolecular structures, resulting In enhanced charge carrier mobilities. © 2010 American Chemical Society.

DOI 10.1021/ja100276x
Citations Scopus - 65
2010 Chang H, Zhang J, Lv L, Wang Z, Yang C, Takahashi I, et al., 'A study on the epitaxial ordering process of the polycaprolactone on the highly oriented polyethylene substrate', Macromolecules, 43 362-366 (2010)

Studies on the influence of foreign surfaces on the crystallization of polymers have demonstrated that the lamellae of the epitaxial polymer in the contact layer could be several ... [more]

Studies on the influence of foreign surfaces on the crystallization of polymers have demonstrated that the lamellae of the epitaxial polymer in the contact layer could be several times thicker than those produced by bulk crystallization under the same condition. It is, however, not clear that how far of the polymer melt from the interface can be affected by the foreign surface and how this effect propagates from the interface into the polymer melt. Therefore, the molecular dynamics of PCL during its epitaxy on an oriented PE substrate was studied. The obtained results show that keeping the samples at temperatures above the bulk melting temperature but below the equilibrium melting point of PCL for a period of time leads to the formation of unusual ordered PCL, which melts at much higher temperature than its bulk crystallized counterpart. It was demonstrated that the ordering process propagates from the interface into the PCL melt. For a sufficient time, all of the PCL chains can be organized into the similar ordered structure, which leads to the final epitaxial crystallization of PCL on the PE substrate with extremely broad lamellae thickness. © 2009 American Chemical Society.

DOI 10.1021/ma902235f
Citations Scopus - 28
2010 Chen Q, Zhang X, Chen T, Wang D, Qian HL, Wang ZH, Wan LJ, 'Substitution effect on the adlayer formation of tetrachloroperylene bisimides on HOPG surface', Surface Science, 604 2078-2083 (2010)

Di-perylene-3,4,9,10-tetracarboxylic acid bisimides (diPBI) is an n-type graphene molecule with nonplanar conformation. The controllable assembly and molecular adlayer structures ... [more]

Di-perylene-3,4,9,10-tetracarboxylic acid bisimides (diPBI) is an n-type graphene molecule with nonplanar conformation. The controllable assembly and molecular adlayer structures of tetrachlorinated diPBI derivatives with different alkyl chains substitutions on highly oriented pyrolytic graphite were studied by scanning tunneling microscopy. When the molecule was substituted by butyl, the formation of multilayer or monolayer can be regulated by the solution concentration. When the molecule was substituted by 2-ethylhexyl, however, it can only form monolayer assembly. The unit cell of 2-ethylhexyl substituted diPBI adlayer was expanded to a rectangular shape compared to that of the butyl substituted diPBI. The steric repulsion of the alkyl chains (straight or branched) substitution is proposed as the key factor to control the adlayer structures of diPBI derivatives. The result is helpful to the design and fabrication of the organic film of chemically synthesized graphene type materials. © 2010 Elsevier B.V. All rights reserved.

DOI 10.1016/j.susc.2010.08.022
Citations Scopus - 4
2010 Li Y, Li C, Yue W, Jiang W, Kopecek R, Qu J, Wang Z, 'Direct functionalization of polycyclic aromatics via radical perfluoroalkylation', Organic Letters, 12 2374-2377 (2010)

Direct functionalization of electron-deficient and electron-rich polycyclic aromatics via copper-mediated radical perfluoroalkylation was achieved in high yields. © 2010 American ... [more]

Direct functionalization of electron-deficient and electron-rich polycyclic aromatics via copper-mediated radical perfluoroalkylation was achieved in high yields. © 2010 American Chemical Society.

DOI 10.1021/ol1007197
Citations Scopus - 35
2010 Wang H, Su H, Qian H, Wang Z, Wang X, Xia A, 'Structure-dependent all-optical switching in graphene-nanoribbon-like molecules: Fully conjugated tri(perylene bisimides)', Journal of Physical Chemistry A, 114 9130-9135 (2010)

We present the structure-dependent nonlinear optical (NLO) properties of fully conjugated tri(perylene bisimides) (triPBIs) toward the understanding of the role of conformational ... [more]

We present the structure-dependent nonlinear optical (NLO) properties of fully conjugated tri(perylene bisimides) (triPBIs) toward the understanding of the role of conformational flexibility and p-electron conjugation in molecular NLO properties of model graphene-nanoribbon (GNR)-like molecules. In the present paper, we report the NLO absorption properties of the triPBIs in toluene excited at 532 nm with nanosecond laser pulses, where the observed transient excited state is determined to be a triplet and presented in the nonlinear process similar to the NLO properties that occur in C60. As a result, the all-optical switching in both visible and near-infrared regions upon excitation at 532 nm was demonstrated, suggesting that the chemically synthesized model GNRs act well as smart all-optical switching devices without the need of external control. Furthermore, Raman spectral measurement was further used to characterize the conjugated structure properties of model compounds of functionalized graphene nanoribbons (F-GNRs), while the dispersion and splitting of the G-band and D-band in both frequency and intensity can help to distinguish the p-conjugation and conformational flexibility of the two different triPBI isomers, showing the opportunity to tailor their optoelectronic properties by precisely controlling the edge orientation, edge width, and chemical termination of the edges in the synthesized F-GNRs. © 2010 American Chemical Society.

DOI 10.1021/jp1056489
Citations Scopus - 25
2010 Zhen Y, Wanga C, Wang Z, 'Tetrachloro-tetra(perylene bisimides): An approach towards N-type graphene nanoribbons', Chemical Communications, 46 1926-1928 (2010)

An extraordinarily large p system based on tetrachloro-tetra-(perylene bisimides) with very broad absorption spectra from the UV to the NIR region and an extremely strong electron... [more]

An extraordinarily large p system based on tetrachloro-tetra-(perylene bisimides) with very broad absorption spectra from the UV to the NIR region and an extremely strong electron-accepting ability has been synthesized from tetrachloro-di(perylene bisimides). © The Royal Society of Chemistry 2010.

DOI 10.1039/b926618f
Citations Scopus - 33
2010 Zhen Y, Yue W, Li Y, Jiang W, Di Motta S, Di Donato E, et al., 'Chiral nanoribbons based on doubly-linked oligo-perylene bisimides', Chemical Communications, 46 6078-6080 (2010)

A facile strategy towards conformationally stable chiral ladder-type oligo-perylene bisimides is established via copper-mediated Ullmann coupling. Absolute configurations are dete... [more]

A facile strategy towards conformationally stable chiral ladder-type oligo-perylene bisimides is established via copper-mediated Ullmann coupling. Absolute configurations are determined with the help of quantum-chemical calculations. © 2010 The Royal Society of Chemistry.

DOI 10.1039/c0cc01011a
Citations Scopus - 16
2010 Di Donato E, Fornari RP, Di Motta S, Li Y, Wang Z, Negri F, 'N-type charge transport and mobility of fluorinated perylene bisimide semiconductors', Journal of Physical Chemistry B, 114 5327-5334 (2010)

The intramolecular and intermolecular charge transport parameters are evaluated quantum chemically for three fluorinated derivatives of perylene bisimide (PBI) semiconductors, two... [more]

The intramolecular and intermolecular charge transport parameters are evaluated quantum chemically for three fluorinated derivatives of perylene bisimide (PBI) semiconductors, two of which feature a twisted PBI core. Charge transfer rates are computed within the Marcus-Levich-Jortner formalism including a single effective mode treated quantum mechanically and are injected in a kinetic Monte Carlo scheme to propagate the charge carrier in the crystal and to estimate charge mobilities at room temperature. The relative order of computed mobilities agrees with the observed trend, and the largest mobility is computed for the planar PBI derivative. It is suggested that thermally induced disorder effects should contribute considerably to the observed large mobility of the planar PBI derivative, while a retardation effect induced by the presence of alternating slow and fast jumps along p-stacked PBI columns is responsible for the lower mobilities of the two twisted derivatives. The computed parameters reveal the subtle interplay between intramolecular and intermolecular contributions to the charge carrier propagation in these organic semiconductors and may guide the design of more efficient architectures. © 2010 American Chemical Society.

DOI 10.1021/jp101040r
Citations Scopus - 55
2010 Wu Y, Zhen Y, Ma Y, Zheng R, Wang Z, Fu H, 'Exceptional intersystem crossing in Di(perylene bisimide)s: A structural platform toward photosensitizers for singlet oxygen generation', Journal of Physical Chemistry Letters, 1 2499-2502 (2010)

Photosensitized reactions of molecular oxygen have found far-reaching applications in various fields, and the development of new photosensitizer compounds is of crucial importance... [more]

Photosensitized reactions of molecular oxygen have found far-reaching applications in various fields, and the development of new photosensitizer compounds is of crucial importance. We here describe a new class of triply linked bay-fused diperylene bisimides (DiPBIs) which exhibited several unique features, rendering them a new structural platform for the development of highly efficient and photostable photosensitizers. (i) The extended p-conjugation shifts its absorption into the bodys therapeutic window. (ii) The nonplanarity of the distorted cores enhances the spin-orbit coupled intersystem crossing. (iii) The long-lasting high-energy T1 state facilitates singlet oxygen generation via energy-transfer reaction between T1 and ground-state oxygen. © 2010 American Chemical Society.

DOI 10.1021/jz1008328
Citations Scopus - 40
2010 Wang Z, Chen X, Ji H, Ma W, Chen C, Zhao J, 'Photochemical cycling of iron mediated by dicarboxylates: special effect of malonate.', Environ Sci Technol, 44 263-268 (2010)
DOI 10.1021/es901956x
Citations Scopus - 31Web of Science - 26
2010 Wang Z, Xie X, Xiao S, Liu J, 'Comparative study of interaction between pyrite and cysteine by thermogravimetric and electrochemical techniques', Hydrometallurgy, 101 88-92 (2010)

Adsorption mechanism of l-cysteine on pyrite was investigated by thermogravimetric and electrochemical techniques. TG curves provided the direct evidence for chemisorption of cyst... [more]

Adsorption mechanism of l-cysteine on pyrite was investigated by thermogravimetric and electrochemical techniques. TG curves provided the direct evidence for chemisorption of cysteine on pyrite surface. Once cysteine adsorbed to pyrite surface, Ecorr(corrosion potential) sharply lowered whereas Icorr(corrosion current) increased rapidly. Pyrite became more susceptible to be oxidized even at lower potential as cysteine was added. However, the mechanism for pyrite oxidation does not fundamentally change, although cysteine can obviously accelerate oxidation rate of pyrite. These findings have important implications for understanding the mechanism of bacterial adhesion to pyrite and even metal sulfide bioleaching. © 2009 Elsevier B.V. All rights reserved.

DOI 10.1016/j.hydromet.2009.11.015
Citations Scopus - 11Web of Science - 10
2010 Wang Z, Xie X, Xiao S, Liu J, 'Adsorption behavior of glucose on pyrite surface investigated by TG, FTIR and XRD analyses', Hydrometallurgy, 102 87-90 (2010)

The interaction of glucose with pyrite has been investigated by a series of surface analyses, such as amounts adsorbed, TG, FTIR and XRD measurements. The adsorption experiment re... [more]

The interaction of glucose with pyrite has been investigated by a series of surface analyses, such as amounts adsorbed, TG, FTIR and XRD measurements. The adsorption experiment reveals that glucose would rapidly adsorb on the pyrite surface within 60 min. However, physical adhesion characterized as multi-molecular layer adsorption may occur based on adsorption isotherm type. All results obtained by TG and FTIR suggest that no adsorption took place after several times of washing. XRD results indicate that crystal structure of pyrite was not obviously destructed after glucose was added. The interplane distances of (111), (400) after interaction between glucose and pyrite were widened, which showed the similar manner with that of before interaction. All these convincing data imply that physical adsorption predominantly governs the interaction of glucose on pyrite. © 2010 Elsevier B.V. All rights reserved.

DOI 10.1016/j.hydromet.2010.01.004
Citations Scopus - 8Web of Science - 7
2009 Zhang L, Tan L, Wang Z, Hu W, Zhu D, 'High-performance, stable organic field-effect transistors based on trans-1,2-(dithieno[2,3-b:3',2'-d]thiophene)ethene', Chemistry of Materials, 21 1993-1999 (2009)

We present here the synthesis, characterization, and transistor performance of three semiconductor materials based on trans-1,2-(dithieno[2,3-b:3&apos;,2&apos;-d] thiophene)ethene... [more]

We present here the synthesis, characterization, and transistor performance of three semiconductor materials based on trans-1,2-(dithieno[2,3-b:3',2'-d] thiophene)ethene derivatives. Although the incorporation of aromatic, alkyl substituents in both ends of trans-1,2-(dithieno[2,3-b:3',2'-d]thiophene)ethene have a negligible effect on the conjugation length and the energy gap, the subtle chemical modification leads to great variations in film microstructures, electronic properties, and packing arrangements. The appropriat ubstituents are capable of providing efficient molecular packing arrangements for high carrier mobility. The phenyl-substituted derivative, compound 3, demonstrates a remarkably high thin film FET performance, with mobility up to 2.0 cm 2 V-1 s-1 and on/off ratio up to 10 8. In addition, the devices show good environmental stability, even after storage in air for 7 months. © 2009 American Chemical Society.

DOI 10.1021/cm900369s
Citations Scopus - 98
2009 Zhang L, Tan L, Hu W, Wang Z, 'Synthesis, packing arrangement and transistor performance of dimers of dithienothiophenes', Journal of Materials Chemistry, 19 8216-8222 (2009)

We present the synthesis, characterization, and transistor performance of a series of semiconductor materials based on dimers of dithienothiophenes with different linkages. The re... [more]

We present the synthesis, characterization, and transistor performance of a series of semiconductor materials based on dimers of dithienothiophenes with different linkages. The relationship between molecular structure, molecular packing arrangement, film morphology, and device performance has been investigated. Subtle changes in molecular structure lead to dramatically different packing modes in the solid state and greatly affect the transport properties of the carriers. The FET devices based on the vinylene-bridged dimers 4 and 5 show mobilities up to 0.08 cm2 V-1 s-1 and 0.89 cm2 V-1 s-1 respectively. © 2009 The Royal Society of Chemistry.

DOI 10.1039/b913340b
Citations Scopus - 27
2009 Li Y, Wang Z, 'Bis-N-annulated quaterrylene: An approach to processable graphene', Organic Letters, 11 1385-1387 (2009)

A new efficient synthetic method toward processable bis-N-annulated quaterrylene from easily available N-annulated perylene derivatives, which is conducted by DDQ/Sc(OTf)3 oxidati... [more]

A new efficient synthetic method toward processable bis-N-annulated quaterrylene from easily available N-annulated perylene derivatives, which is conducted by DDQ/Sc(OTf)3 oxidative coupling and ring fusion, is reported. In light of the good processability and the strong electron-donating ability, which is evidenced from the low oxidative potentials, bis-N-annulated quaterrylene is very promising for use as functional components in molecular devices. © 2009American Chemical Society.

DOI 10.1021/ol9002064
Citations Scopus - 68
2009 Zhen Y, Qian H, Xiang J, Qu J, Wang Z, 'Highly regiospecific synthetic approach to monobay-functionalized perylene bisimide and Di(perylene bisimide)', Organic Letters, 11 3084-3087 (2009)

Monobay-dichlorinated perylene bisimide and di pery lene bisimide have been regiospecifically synthesized from tetrachlorinated perylene bisimide in different copper-mediated reac... [more]

Monobay-dichlorinated perylene bisimide and di pery lene bisimide have been regiospecifically synthesized from tetrachlorinated perylene bisimide in different copper-mediated reaction conditions, thus opening a new avenue to their monobay-functionalization. © 2009 American Chemical Society.

DOI 10.1021/ol901168k
Citations Scopus - 40
2009 Tan L, Zhang L, Jiang X, Yang X, Wang L, Wang Z, et al., 'A densely and uniformly packed organic semiconductor based on annelated ß-trithiophenes for high-performance thin film transistors', Advanced Functional Materials, 19 272-276 (2009)

A novel semiconductor based on annelated ¿Ö-trithiophenes is presented, possessing an extraordinary compressed packing mode combining edge-to-face p-p interactions and S.. .S inte... [more]

A novel semiconductor based on annelated ¿Ö-trithiophenes is presented, possessing an extraordinary compressed packing mode combining edge-to-face p-p interactions and S.. .S interactions in single crystals, which is favorable for more effective charge transporting. Accordingly, the device incorporating this semiconductor shows remarkably high charge carrier mobility, as high as 0.89 cm2V-1 s-1 and an on/off ratio of 4.6 × 107 for vacuum-deposited thin films. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA.

DOI 10.1002/adfm.200800933
Citations Scopus - 81
2009 Wang Z, Ma W, Chen C, Zhao J, 'Light-assisted decomposition of dyes over iron-bearing soil clays in the presence of H2O2', JOURNAL OF HAZARDOUS MATERIALS, 168 1246-1252 (2009)
DOI 10.1016/j.jhazmat.2009.02.160
Citations Scopus - 35Web of Science - 30
2009 Tan L, Jiang W, Jiang L, Jiang S, Wang Z, Yan S, Hu W, 'Single crystalline microribbons of perylo [1,12-b,c,d] selenophene for high performance transistors', Applied Physics Letters, 94 (2009)

Micrometer sized single crystalline ribbons of a Se-heterocyclic annelated perylene were prepared by drop casting and physical vapor transport techniques. The crystals of the Se-h... [more]

Micrometer sized single crystalline ribbons of a Se-heterocyclic annelated perylene were prepared by drop casting and physical vapor transport techniques. The crystals of the Se-heterocyclic annelated perylene showed near planar molecular conformation, which regularly stacked along b -axis with SeSe contacts at 3.49 Å. Single crystal transistors of individual ribbon were fabricated by "gold layer glue" technique. Over 90% transistors exhibited mobility >1.6 cm2 V-1 s-1, the highest mobility approaching 2.66 cm2 V-1 s-1. The top performance indicated the bright prospect of this material in organic electronics. © 2009 American Institute of Physics.

DOI 10.1063/1.3120769
Citations Scopus - 32
2009 Qian H, Yue W, Zhen Y, Di Motta S, Di Donato E, Negri F, et al., 'Heterocyclic annelated di(perylene bisimide): Constructing bowl-shaped perylene bisimides by the combination of steric congestion and ring strain', Journal of Organic Chemistry, 74 6275-6282 (2009)

(Chemical Equation Presented) In this paper, we present the synthesis of S- and N-heterocyclic annelated di(perylene bisimide) with extraordinary doubly bowl-shaped structures. Th... [more]

(Chemical Equation Presented) In this paper, we present the synthesis of S- and N-heterocyclic annelated di(perylene bisimide) with extraordinary doubly bowl-shaped structures. The structures of fused PBI bowls confirmed by singlecrystal X-ray structure analysis and temperature-dependent 1H NMR are realized by the introduction of the steric congestion in nonbay regions and by the concurrent formation of the five-membered heterorings strain in bay regions. On the basis of the geometry obtained from the X-ray analysis, the maximum POAV1 pyramidalization angle is found in N-heterocyclic annelated diPBI 7, as large as 4.7°, indicating the formation of two PBI bowls with significant curvatures. Furthermore, to assist the electrochemical and spectroscopic characterization of the two bowl-shaped derivatives and to assess the influence of heteroatoms on the bowl curvature, quantum-chemically optimized atomic structures, electronic properties, and optical signatures were computed with density functional theory. © 2009 American Chemical Society.

DOI 10.1021/jo901285k
Citations Scopus - 48
2009 Jiang S, Qian H, Liu W, Wang C, Wang Z, Yan S, Zhu D, 'Vapor phase epitaxy of perylo[1,12-b,c,d]thiophene on highly oriented polyethylene thin films', Macromolecules, 42 9321-9324 (2009)

Epitaxial crystallization of PTH on highly oriented PE substrate from vapor phase has been achieved. The epitaxial growth ofPTHon highly oriented PE substrate leads to the formati... [more]

Epitaxial crystallization of PTH on highly oriented PE substrate from vapor phase has been achieved. The epitaxial growth ofPTHon highly oriented PE substrate leads to the formation of lathlikePTH crystals. The lathlikePTHcrystals exhibit well-ordered structure with their long axes preferentially parallel to the chain direction of the PE substrate crystals, while a small part of PTH lathlike crystals aligned with their long axes perpendicular to the chain direction of the PE. Electron diffraction further demonstrates that the epitaxial crystallization ofPTHon oriented PE substrate results in an alignment ofPTHwith the c-and b-axes in the film plane. The c-axis ofPTHis oriented either perpendicular, preferentially, or parallel, less frequently, to the PE chain direction. The former originates from a two-dimensional lattice matching, while the latter is based only on a one-dimensional intermolecular matching. The observed epitaxial growth provides an effective way for preparing large area well-arranged PTH films with unique crystalline structure. © 2009 American Chemical Society.

DOI 10.1021/ma9019762
Citations Scopus - 23
2009 Li Z, Zhi L, Lucas NT, Wang Z, 'Triangle-shaped polycyclic aromatics based on tribenzocoronene: facile synthesis and physical properties', Tetrahedron, 65 3417-3424 (2009)

A series of triangle-shaped polycyclic aromatics have been developed according to a facile synthetic protocol with high yields. As revealed by X-ray single crystal data, their mol... [more]

A series of triangle-shaped polycyclic aromatics have been developed according to a facile synthetic protocol with high yields. As revealed by X-ray single crystal data, their molecular conformation and packing arrangement are significantly influenced by the electronic properties and steric bulk of peripheral subunits. The 'saddle'-shaped hexahalotribenzocoronenes (ClTBC and FTBC) possess C2symmetric structures and can self-assemble into well-defined columnar structures, dramatically different from hexabutyoxytribenzocoronene (TBC), which adopts a C3symmetric 'double-concave' structure and less efficient packing arrangement. In the compound trithiophenocoronene (TTC), the five-membered corner rings produce a more open bay-region periphery alleviating intramolecular steric congestion. As a result, the molecule adopts an almost planar conformation. © 2009 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.tet.2009.02.042
Citations Scopus - 15
2009 Shi Y, Qian H, Lucas NT, Xu W, Wang Z, 'Synthesis of a three-dimensional spiro-annulated polycyclic aromatic hydrocarbon', Tetrahedron Letters, 50 4110-4113 (2009)

We describe the results of our investigation on the preparation, structural characterization, and optical properties of a spiro-annulated polycyclic aromatic hydrocarbon prepared ... [more]

We describe the results of our investigation on the preparation, structural characterization, and optical properties of a spiro-annulated polycyclic aromatic hydrocarbon prepared by the cyclodehydrogenation of a hexa{2-(9,9'-spirobifluorenyl)}benzene precursor molecule. Single-crystal X-ray diffraction analysis reveals that the anthracene backbone adopts one of the largest end-to-end twists thus far reported. © 2009 Elsevier Ltd. All rights reserved.

DOI 10.1016/j.tetlet.2009.04.109
Citations Scopus - 6
2008 Jiang W, Qian H, Li Y, Wang Z, 'Heteroatom-annulated perylenes: Practical synthesis, photophysical properties, and solid-state packing arrangement', Journal of Organic Chemistry, 73 7369-7372 (2008)

(Chemical Equation Presented) A practical strategy for the preparation of a series of heterocyclic annulated perylenes in good yields is presented. UV-vis absorption spectra indic... [more]

(Chemical Equation Presented) A practical strategy for the preparation of a series of heterocyclic annulated perylenes in good yields is presented. UV-vis absorption spectra indicate hypsochromic shift of the absorption maxima relative to the corresponding parent perylene. Single-crystal X-ray diffraction analysis reveals that they all adopt planar conformation, but the solid-state packing arrangements are significantly altered by annulation of various heterocycles. © 2008 American Chemical Society.

DOI 10.1021/jo8012622
Citations Scopus - 82
2008 Chen Q, Chen T, Pan GB, Yan HJ, Song WG, Wan LJ, et al., 'Structural selection of graphene supramolecular assembly oriented by molecular conformation and alkyl chain', Proceedings of the National Academy of Sciences of the United States of America, 105 16849-16854 (2008)

Graphene molecules, hexafluorotribenzo[a,g,m]coronene with n-carbon alkyl chains (FTBC-Cn, n = 4, 6, 8, 12) and Janus-type &quot;double-concave&quot; conformation, are used to fab... [more]

Graphene molecules, hexafluorotribenzo[a,g,m]coronene with n-carbon alkyl chains (FTBC-Cn, n = 4, 6, 8, 12) and Janus-type "double-concave" conformation, are used to fabricate self-assembly on highly oriented pyrolytic graphite surface. The structural dependence of the self-assemblies with molecular conformation and alkyl chain is investigated by scanning tunneling microscopy and density functional theory calculation. An interesting reverse face "up-down" way is observed in FTBC-C4 assembly due to the existence of hydrogen bonds. With the increase of the alkyl chain length and consequently stronger van der Waals interaction, the molecules no longer take alternating "up-down" orientation in their self-assembly and organize into various adlayers with lamellar, hexagonal honeycomb, and pseudohoneycomb structures based on the balance between intermolecular and molecule-substrate interactions. The results demonstrate that the featured "double- concave" molecules are available block for designing graphene nanopattern. From the results of scanning tunneling spectroscopy measurement, it is found that the electronic property of the featured graphene molecules is preserved when they are adsorbed on solid surface. © 2008 by The National Academy of Sciences of the USA.

DOI 10.1073/pnas.0809427105
Citations Scopus - 34
2008 Wang Z, Ma W, Chen C, Zhao J, 'Photochemical coupling reactions between Fe(III)/Fe(II), Cr(VI)/Cr(III), and polycarboxylates: Inhibitory effect of Cr species', Environmental Science and Technology, 42 7260-7266 (2008)

The roles of chromium species on photochemical cycling of iron and mineralization of polycarboxylates are examined in the presence of Cr(VI) or Cr(III) at pH 2.2-4.0. Under UV irr... [more]

The roles of chromium species on photochemical cycling of iron and mineralization of polycarboxylates are examined in the presence of Cr(VI) or Cr(III) at pH 2.2-4.0. Under UV irradiation, Cr(III) altered the redox equilibrium of iron species, leading to the shift of the photosteady state toward Fe(II). After a longer time of illumination, total organic carbon (TOC) approached a steady state in the presence of Cr(III) or Cr(VI), whereas oxalate was thoroughly mineralized in the absence of Cr species. The TOC of steady state was closely related to the kind of polycarboxylates, Cr species dosages, pH and O2atmosphere, but hardly affected by more addition of Fe(III). ESI-MS data indicates that several Cr-oxalate complexes formed in the photochemical reactions, which are responsible for protecting oxalate against further oxidation. A mechanism is proposed for the inhibitory effect of Cr species on oxidation of oxalate and Fe(II). The present study may provide a new insight into the dual environmental effects induced by Cr contaminants especially at heavily chromium-contaminated and dissolved organic matter (DOM)-rich sites. © 2008 American Chemical Society.

DOI 10.1021/es801379j
Citations Scopus - 32Web of Science - 29
2008 Qian H, Negri F, Wang C, Wang Z, 'Fully conjugated tri(perylene bisimides): An approach to the construction of n-type graphene nanoribbons', Journal of the American Chemical Society, 130 17970-17976 (2008)

We present an experimental study encompassing synthesis and characterization of fully conjugated tri(perylene bisimides) (triPBIs), having 19 six-membered carbon rings in the core... [more]

We present an experimental study encompassing synthesis and characterization of fully conjugated tri(perylene bisimides) (triPBIs), having 19 six-membered carbon rings in the core and six imide groups at the edges. Two structural isomers of triPBIs resulting from the two probable coupling positions were successfully separated by HPLC. To assist the identification of the two structural isomers, quantum-chemical calculations of electronic structure, NMR, and optical spectra were carried out. Calculations predict stable helical and nonhelical configurations for both triPBIs isomers and allow the assignment of triPBIs 6 unequivocally to the most bathochromically shifted absorption spectrum. Increasing the number of PBI units in oligo-PBIs leads to an expansion of the p system, in turn associated with a reduction of the transport and optical band gaps, and a remarkable increase in electron affinities, which make oligo-PBIs promising n-type functional components in optoelectronic devices. © 2008 American Chemical Society.

DOI 10.1021/ja807803j
Citations Scopus - 135
2008 Jiang L, Gao J, Wang E, Li H, Wang Z, Hu W, Jiang L, 'Organic single-crystalline ribbons of a rigid "H"-type anthracene derivative and high-performance, short-channel field-effect transistors of individual micro/ nanometer-sized ribbons fabricated by an "organic ribbon mask" technique', Advanced Materials, 20 2735-2740 (2008)

The &quot;H&quot;-type anthracene derivative was synthesized by coupling 9-ethynylanthracene with 9-bromoanthracene. The presence of the triple bond in the molecules avoided the r... [more]

The "H"-type anthracene derivative was synthesized by coupling 9-ethynylanthracene with 9-bromoanthracene. The presence of the triple bond in the molecules avoided the repulsion of the hydrogen atoms in adjacent anthracene rings, which lead to a rigid, planar molecular structure. It was found that the ionization potential (IP) of the derivative was larger than that of pentacene, implying the good oxidation stability of the compound. Transistors based on individual ribbons were fabricated in situ through a organic ribbon mask method. The channel length of the transistor was scaled down to sub-micrometer level using the method. The high performance of the transistors demonstrated that the organic ribbon mask method was highly feasible in device fabrication and H-type molecular configuration is a good prototype of new organic semiconductors.

DOI 10.1002/adma.200800341
Citations Scopus - 126
2008 Tang Q, Jiang L, Tong Y, Li H, Liu Y, Wang Z, et al., 'Micrometer- and nanometer-sized organic single-crystalline transistors', Advanced Materials, 20 2947-2951 (2008)

The use of micrometer and nanometer-sized organic single crystals to fabricate devices can retain all the advantages of single crystals, avoid the difficulties of growing large cr... [more]

The use of micrometer and nanometer-sized organic single crystals to fabricate devices can retain all the advantages of single crystals, avoid the difficulties of growing large crystals, and provide a way to characterize organic semiconductors more efficiently. Moreover, the effective use of such "small" crystals will be beneficial to nanoelectronics. Here we review the recent progress of organic single-crystalline transistors based on micro-/nanometer-sized structures, namely fabrication methods and related technical issues, device properties, and current challenges. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA,.

DOI 10.1002/adma.200800669
Citations Scopus - 148
2008 Li Y, Tan L, Wang Z, Qian H, Shi Y, Hu W, 'Air-stable n-type semiconductor: Core-perfluoroalkylated perylene bisimides', Organic Letters, 10 529-532 (2008)

A series of core-perfluoroalkylated perylene bisimides (PBIs) have been efficiently synthesized by copper-mediated perfluoroalkylation of dibrominated PBIs. Their aromatic cores a... [more]

A series of core-perfluoroalkylated perylene bisimides (PBIs) have been efficiently synthesized by copper-mediated perfluoroalkylation of dibrominated PBIs. Their aromatic cores are highly twisted due to the steric encumbrance in the bay regions as revealed by single-crystal X-ray analysis. The organic field-effect transistors (OFETs) incorporating these new n-type semiconductors show remarkable air-stability and good field effect mobility. © 2008 American Chemical Society.

DOI 10.1021/ol703046w
Citations Scopus - 113
2008 Shi Y, Qian H, Li Y, Yue W, Wang Z, 'Copper-mediated domino process for the synthesis of tetraiodinated di(perylene bisimide)', Organic Letters, 10 2337-2340 (2008)

(Chemical Equation Presented) Tetraiodinated di(perylene bisimide) has been prepared from tetrabrominated perylene bisimide by the combination of Ullmann-type coupling, C-H transf... [more]

(Chemical Equation Presented) Tetraiodinated di(perylene bisimide) has been prepared from tetrabrominated perylene bisimide by the combination of Ullmann-type coupling, C-H transformation, and halogen-exchange. The crystal structure analysis confirmed that the aromatic core is quite distorted because of the electrostatic repulsion and steric encumbrance of iodine substituents in the bay regions. © 2008 American Chemical Society.

DOI 10.1021/ol800482y
Citations Scopus - 44
2007 Sun Y, Tan L, Jiang S, Qian H, Wang Z, Yan D, et al., 'High-performance transistor based on individual single-crystalline micrometer wire of perylo[1,12-6,c,d]thiophene', Journal of the American Chemical Society, 129 1882-1883 (2007)

We have first investigated the thin-film field-effect behavior of perylo[1,12-b,c,d]thiophene by vacuum evaporation technique, which exhibits a moderate mobility of 0.05 cm2 V-1 s... [more]

We have first investigated the thin-film field-effect behavior of perylo[1,12-b,c,d]thiophene by vacuum evaporation technique, which exhibits a moderate mobility of 0.05 cm2 V-1 s-1, an on/off ratio of 105, and a low threshold voltage of -6.3 V at room temperature. Moreover, we have grown its single-crystalline micrometer wires and successfully applied them to transistors. A high mobility up to 0.8 cm2 V-1 s-1 has been achieved. The extraordinary solid-state packing arrangement with the likelihood of double-channel fashion induced by marked S¿S interactions may contribute to the high performance. Copyright © 2007 American Chemical Society.

DOI 10.1021/ja068079g
Citations Scopus - 118
2007 Fogel Y, Kastler M, Wang Z, Andrienko D, Bodwell GJ, Müllen K, 'Electron-deficient N-heteroaromatic linkers for the elaboration of large, soluble polycyclic aromatic hydrocarbons and their use in the synthesis of some very large transition metal complexes', Journal of the American Chemical Society, 129 11743-11749 (2007)

The selective oxidation of the perimeter of an extended polycyclic aromatic hydrocarbon (PAH), namely a six-fold tert-butylated tetrabenzo[bc,ef,hi,uv] ovalene, led to the formati... [more]

The selective oxidation of the perimeter of an extended polycyclic aromatic hydrocarbon (PAH), namely a six-fold tert-butylated tetrabenzo[bc,ef,hi,uv] ovalene, led to the formation of an a-diketone. The newly installed carbonyl centers allowed this building block to be converted into the largest known heteroatom-containing PAHs (up to 224 atoms in the aromatic core) by way of the quinoxaline ring condensation reaction. The tert-butyl substituents caused a distortion of the usually planar aromatic frameworks, which hampered the aggregation tendency of the extended aromatic p-systems and led to extraordinarily high solubilities. All of the systems described here, even the giant phthalocyanine, could thus be purified using standard chromatographic techniques and characterized using typical spectroscopic methods. For the first time, fully resolved 1H NMR spectra of soluble, diamagnetic, 98- and 104-atom-containing aromatic systems are presented. The computed and experimental UV/vis spectra emphasize the dependence of the characteristic a-, p-, and ß-bands upon the size of the PAHs. It was also possible to obtain the largest known ligand to yet be complexed around a ruthenium center. A quadrupolar solvatochromic effect was observed when two donating PAH moieties were fused to an accepting quinoxaline center, in which case the photoluminescence spanned a range of about 80 nm. Electrochemical properties of the new nanographenes were investigated using cyclic voltammetry, and this showed quasi-reversible reductions. © 2007 American Chemical Society.

DOI 10.1021/ja072521t
Citations Scopus - 81
2007 Qian H, Wang Z, Yue W, Zhu D, 'Exceptional coupling of tetrachloroperylene bisimide: Combination of ullmann reaction and C-H transformation', Journal of the American Chemical Society, 129 10664-10665 (2007)

We present the facile one-pot synthesis of novel triply linked diperylene bisimide (diPBI) and tetrachlorinated diperylene bisimide (4CldiPBI) by l-proline promoted CuI-involved c... [more]

We present the facile one-pot synthesis of novel triply linked diperylene bisimide (diPBI) and tetrachlorinated diperylene bisimide (4CldiPBI) by l-proline promoted CuI-involved coupling of tetrachloro-PBI, which represents the first step toward the completely bay-region fused oligo-PBIs. The triply linked fused diPBIs display the broad absorption with high extinction coefficients in the region of visible light and the extremely strong electron-accepting ability, which is very promising for use as functional components of photovoltaic devices. Copyright © 2007 American Chemical Society.

DOI 10.1021/ja0740972
Citations Scopus - 98
2007 Li Z, Lucas NT, Wang Z, Zhu D, 'Facile synthesis of Janus "double-concave" tribenzo[a,g,m] coronenes', Journal of Organic Chemistry, 72 3917-3920 (2007)

(Chemical Equation Presented)Hexabutoxytribenzo[a,g,m]coronenes have been prepared in three steps from readily accessible hexabutoxytriphenylene. Single-crystal X-ray diffraction ... [more]

(Chemical Equation Presented)Hexabutoxytribenzo[a,g,m]coronenes have been prepared in three steps from readily accessible hexabutoxytriphenylene. Single-crystal X-ray diffraction analysis reveals that these molecules can adopt an extraordinary "double-concave" conformation that makes them ideal hosts for the binding of different guest molecules at each face. © 2007 American Chemical Society.

DOI 10.1021/jo0701029
Citations Scopus - 12
2006 Qian H, Liu C, Wang Z, Zhu D, 'S-heterocyclic annelated perylene bisimide: Synthesis and co-crystal with pyrene', Chemical Communications, 4587-4589 (2006)

An S-heterocyclic annelated perylene bisimide (PBI) has been prepared from readily available tetrachloro-PBI by a one-step palladium-catalyzed reaction; when co-crystallized with ... [more]

An S-heterocyclic annelated perylene bisimide (PBI) has been prepared from readily available tetrachloro-PBI by a one-step palladium-catalyzed reaction; when co-crystallized with pyrene it gives a unique columnar arrangement of 1: 2 complexes. © The Royal Society of Chemistry 2006.

DOI 10.1039/b610765f
Citations Scopus - 65
2006 Liu J-S, Wang Z-H, Chen H, Zhang Y-H, 'Interfacial electrokinetic characteristics before and after bioleaching microorganism adhesion to pyrite', TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA, 16 676-680 (2006)
DOI 10.1016/S1003-6326(06)60120-9
Citations Scopus - 11Web of Science - 3
2006 Liu J-S, Wang Z-H, Li B-M, Zhang Y-H, 'Interaction between pyrite and cysteine', TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA, 16 943-946 (2006)
DOI 10.1016/S1003-6326(06)60356-7
Citations Scopus - 12Web of Science - 12
2006 Wasserfallen D, Kastler M, Pisula W, Hofer WA, Fogel Y, Wang Z, Müllen K, 'Suppressing aggregation in a large polycyclic aromatic hydrocarbon', Journal of the American Chemical Society, 128 1334-1339 (2006)

With the approach presented herein, a large aromatic p-system is synthesized, which shows extraordinarily high solubility and an effective suppression of aggregation. This was due... [more]

With the approach presented herein, a large aromatic p-system is synthesized, which shows extraordinarily high solubility and an effective suppression of aggregation. This was due to a distortion of the aromatic core by bulky tert-butyl groups and the solubilizing effects of alkyl chains in the corona of the aromatic core. Therefore not only the processing and cleaning of the materials with standard laboratory techniques became possible, but moreover the first structure-rich UV/vis and a resolved 1H NMR spectra for an aromatic system two times larger than hexa-peri-hexabenzocoronene were recorded. The bulk properties in an extruded fiber as well as on the surface showed a columnar self-assembly including a phase in which a homeotropic alignment on a substrate was observed, which turns the material into an interesting candidate for future applications in electronic devices. © 2006 American Chemical Society.

DOI 10.1021/ja056782j
Citations Scopus - 95
2005 Wang Z, Dötz F, Enkelmann V, Müllen K, '"Double-concave" graphene: Permethoxylated hexa-peri- hexabenzocoronene and its cocrystals with hexafluorobenzene and fullerene', Angewandte Chemie - International Edition, 44 1247-1250 (2005)

Extremely nonplanar permethoxylated hexa-peri-hexabenzocoronene can be prepared by using a facile ferric chloride cyclodehydrogenation procedure. The combination of a rigid &quot;... [more]

Extremely nonplanar permethoxylated hexa-peri-hexabenzocoronene can be prepared by using a facile ferric chloride cyclodehydrogenation procedure. The combination of a rigid "double-concave" aromatic core with 18 flexible methoxy groups at the periphery makes it a remarkable host molecule, as revealed by single-crystal analysis of its crystalline inclusion complexes with hexafluorobenzene and fullerene guest molecules (see crystal structure). © 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI 10.1002/anie.200461445
Citations Scopus - 60
2004 Wu J, Watson MD, Zhang L, Wang Z, Müllen K, 'Hexakis(4-iodophenyl)-peri-hexabenzocoronene - A Versatile Building Block for Highly Ordered Discotic Liquid Crystalline Materials', Journal of the American Chemical Society, 126 177-186 (2004)

Hexakis (4-iodophenyl)-peri-hexabenzocoronene (5), a novel functionalizable mesogenic building block, was prepared by rational multistep synthesis. Although sparingly soluble in c... [more]

Hexakis (4-iodophenyl)-peri-hexabenzocoronene (5), a novel functionalizable mesogenic building block, was prepared by rational multistep synthesis. Although sparingly soluble in common solvents, it can be obtained in pure form and then functionalized via Hagihara-Sonogashira coupling to give a series of highly ordered columnar liquid crystalline molecules 14a-c. The total synthesis involves five 6-fold transformations, all in excellent to near quantitative isolated yields. Their thermotropic liquid crystalline behavior was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD). Compared to the normal alkyl-subsituted hexabenzocoronenes (HBCs), 14a-c exhibit more highly ordered columnar mesophases, including three-dimensionally ordered super-structures (helical columnar mesophase). These could arise from additional intracolumnar p-p interactions between, and space-filling requirements introduced by, the rigid-rod side groups. Atomic force microscopy (AFM) revealed self-assembled bundles of columnar aggregates in spin-coated films and isolated several-micron-long nanoribbons composed of a defined number of columns in drop cast films.

Citations Scopus - 178
2004 Samorì P, Yin X, Tchebotareva N, Wang Z, Pakula T, Jäckel F, et al., 'Self-Assembly of Electron Donor-Acceptor Dyads into Ordered Architectures in Two and Three Dimensions: Surface Patterning and Columnar "Double Cables"', Journal of the American Chemical Society, 126 3567-3575 (2004)

We report the synthesis and characterization of covalent dyads and multiads of electron acceptors (A) and donors (D), with the purpose of exploiting their nanophase separation beh... [more]

We report the synthesis and characterization of covalent dyads and multiads of electron acceptors (A) and donors (D), with the purpose of exploiting their nanophase separation behavior toward (a) two-dimensional (2D) surface patterning with well-defined integrated arrays of dissimilar molecular electronic features and (b) bulk self-assembly to noncovalent columnar versions of the so-called "double cable" systems, the likes of which could eventually provide side-by-side percolation pathways for electrons and holes in solar cells. Soluble, alkylated hexa-peri-hexabenzocoronenes (HBCs) bearing tethered anthraquinones (AQs) are shown by scanning tunneling microscopy (STM) to self-assemble at the solution-graphite interface into either defect-rich polycrystalline monolayers or extended 2D crystalline domains, depending on the number of tethered AQs. In the bulk, the thermal stability of the room-temperature HBC columnar phase is increased, which is attributed to the desired nanotriphase separation of HBC columns, insulating alkyl sheaths, and AQ units. Homeotropic alignment (columns normal to surfaces), predicted to be ideal for potential exploitation of such "double cables" in photovoltaic devices, is demonstrated.

DOI 10.1021/ja038648+
Citations Scopus - 95
2004 Wang Z, Tomovic Z, Kastler M, Pretsch R, Negri F, Enkelmann V, Müllen K, 'Graphitic molecules with partial "Zig/Zag" periphery', Journal of the American Chemical Society, 126 7794-7795 (2004)

A new synthetic protocol that affords novel hexa-peri-hexabenzocoronene (HBC) derivatives with partial &quot;zig/zag&quot; periphery and dramatically different electronic properti... [more]

A new synthetic protocol that affords novel hexa-peri-hexabenzocoronene (HBC) derivatives with partial "zig/zag" periphery and dramatically different electronic properties has been developed, which represents an important step toward understanding structure-property relationships of graphitic materials. The scope of this methodology was broadened by application to a much larger polycyclic aromatic hydrocarbon (PAH) with a more extended "zig/zag" character. Copyright © 2004 American Chemical Society.

DOI 10.1021/ja048580d
Citations Scopus - 70
2004 Wu J, Watson MD, Tchebotareva N, Wang Z, Müllen K, 'Oligomers of hexa-peri-hexabenzocoronenes as "super- oligophenylenes": Synthesis, electronic properties, and self-assembly', Journal of Organic Chemistry, 69 8194-8204 (2004)

Hexa-peri-hexabenzocoronene (HBC) is a remarkable polycyclic aromatic hydrocarbon and is often called &quot;superbenzene&quot; because of its similarity to benzene. In this articl... [more]

Hexa-peri-hexabenzocoronene (HBC) is a remarkable polycyclic aromatic hydrocarbon and is often called "superbenzene" because of its similarity to benzene. In this article we present the facile synthesis of oligomers of HBC, up to trimers (3, 4, 5a-c) with different modes of connection. UV-vis and fluorescence spectroscopy studies reveal that the oligomers are electronically decoupled. This arises from the small atomic orbital coefficients of the bridge-head carbon atoms, the large torsion angle between the HBC units, and the large distance of interacting transition dipoles due to the size of the HBC chromophore. For comparison, a methylene-bridged HBC dimer 6, so-called "superfluorene", was prepared. The induced planarity improves p-conjugation and suppresses the geometrical relaxation of the backbone upon electronic excitation, leading to a prominent 0-0 transition band in the fluorescence spectra. The self-assembly of the oligomers and of superfluorene 6 was studied by wide-angle X-ray diffraction (WAXD) in the bulk state, and ordered columnar stacking occurs in the HBC dimer 3, p-HBC trimer 4, and superfluorene 6. Measurements of shear-aligned samples show that, despite increasing aspects ratio by linear entrainment of disks, the anitropic element that is subject to alignment by shear is the supramolecular columns.

DOI 10.1021/jo0490301
Citations Scopus - 52
2004 Liu JS, Xia HB, Wang ZH, 'Treatment of waste water from powder blue production with sulphur precipitation-coagulation', Zhongnan Gongye Daxue Xuebao/Journal of Central South University of Technology, 35 941-944 (2004)

Treatment of waste water raised from powder blue production was investigated in this paper. The dosage of alkali used to adjust pH was given, and the influence of NH3on solution c... [more]

Treatment of waste water raised from powder blue production was investigated in this paper. The dosage of alkali used to adjust pH was given, and the influence of NH3on solution chemistry was studied. The scheme of sulphur-precipitation coagulation was carried by using the waste water raised from noble metal production. The results show that when the mix is below 10:1 between waste water raised from powder blue production and from noble metal production, it's no need to add Na2S to make waste water in fit with national drainage standards; but it needs to add Na2S if the mix is above 10:1. The orthogonal experiment results show that the residual heavy metal is affected by dosage of Na2S, dosage of PFS, and pH, respectively in a descent order, and when Na2S dosage is 0.146 g/L and PFS dosage is 1.596 g/L at pH 7.0, the content of heavy metal in waste water can fit with that of national drainage standards.

Citations Scopus - 3
2004 Wang Z, Watson MD, Wu J, Müllen K, 'Partially stripped insulated nanowires: A lightly substituted hexa-peri-hexabenzocoronene-based columnar liquid crystal', Chemical Communications, 4 336-337 (2004)

We present the facile preparation and characterization of the first ¿unwrapped¿ hexa-peri-hexabenzocoronene derivative, which forms a stable columnar liquid crystalline mesophase ... [more]

We present the facile preparation and characterization of the first ¿unwrapped¿ hexa-peri-hexabenzocoronene derivative, which forms a stable columnar liquid crystalline mesophase with a practically accessible isotropization temperature. © 2004 The Royal Society of Chemistry.

DOI 10.1039/b311651d
Citations Scopus - 40
2004 Liu JS, Xia HB, Wang ZH, Hu YH, 'Bacterial oxidation activity in heap leaching', JOURNAL OF CENTRAL SOUTH UNIVERSITY OF TECHNOLOGY, 11 375-379 (2004)
DOI 10.1007/s11771-004-0078-2
Citations Scopus - 6Web of Science - 5
2004 Wang Z, Enkelmann V, Negri F, Müllen K, 'Rational design of helical, columnar packing in single crystals', Angewandte Chemie - International Edition, 43 1972-1975 (2004)

A highly ordered helical columnar packing in single crystals (see picture) can be generated from a simple and nonchiral aromatic system based on pyrene by rational design. The pac... [more]

A highly ordered helical columnar packing in single crystals (see picture) can be generated from a simple and nonchiral aromatic system based on pyrene by rational design. The packing preference can be attributed to the combined effect of maximized dipole-dipole interaction and the compatible accommodation of bulky tert-butyl groups.

DOI 10.1002/anie.200353245
Citations Scopus - 36
2003 Wu J, Gherghel L, Watson MD, Li J, Wang Z, Simpson CD, et al., 'From branched polyphenylenes to graphite ribbons', Macromolecules, 36 7082-7089 (2003)

This article presents the synthesis of graphitic nanoribbons (~1 nm wide), containing extended conjugated all-benzenoid segments. These were obtained by intramolecular oxidative c... [more]

This article presents the synthesis of graphitic nanoribbons (~1 nm wide), containing extended conjugated all-benzenoid segments. These were obtained by intramolecular oxidative cyclodehydrogenation of soluble branched polyphenylenes 6, which were prepared by repetitive Diels-Alder cycloaddition of 1,4-bis(2,4,5-triphenylcyclopentadienone-3-yl)benzene (1) and diethynylterphenyl (5) in good yield. While insolubility of the obtained graphite ribbons 7 precluded standard spectroscopic structure elucidation, the electronic and vibrational properties were probed by solid-state UV-vis, Raman, and infrared spectroscopy. A wide and unstructured absorption band covering the visible range of the electronic spectrum (¿max ~ 800 nm) is observed, confirming the highly extended conjugated framework. The structure proof of the ribbon-type polymer is supported by the inclusion of appropriate model compounds. The profile of the visible Raman spectrum of the material is similar to that of a discrete polycyclic aromatic hydrocarbon (PAH) C222H42, characterized by two strong bands (at 1603 and 1322 cm-1), corresponding to the G and D bands of graphite. The obtained graphite ribbons are not linear but rather contain "kinks" due to the structural design of the polyphenylene precursor. High-resolution transmission electron microscopy (HRTEM) images of the graphite ribbons 7 disclose two different domains: one is an ordered graphite layer structure with a layer distance of ca. 3.8 Å, and one is disordered due to the existence of "kinks" in the obtained polymers and/or random stacking of graphite ribbons. Attempts to make linear analogues are so far unsuccessful, emphasizing the critical importance of the geometry of the polyphenylene scaffold to successful oxidative cyclodehydrogenation.

DOI 10.1021/ma0257752
Citations Scopus - 100
1999 Wang Z, Xiong Y, Sun Y, Kong F, 'Femtosecond Time-Resolved Fluorescence Spectra of LDS751', Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis, 19 258-259 (1999)

The femtosecond time-resolved fluorescence depletion method has been introduced. In this method two beams of femtosecond laser was used. One excited the sample molecular to emit f... [more]

The femtosecond time-resolved fluorescence depletion method has been introduced. In this method two beams of femtosecond laser was used. One excited the sample molecular to emit fluorescence. Then after specified time delay the second laser beam was introduced to deplete the fluorescence through the stimulate emission process. This method has been applied to LDS751 molecules in solution and its time-resolved fluorescence spectrum has been obtained.

1998 He Y, Xiong Y, Wang Z, Zhu Q, Kong F, 'A Theoretical Study on Ultrafast Vibrational Relaxation of Dye Molecule in Solution', Acta Physico - Chimica Sinica, 14 115-120 (1998)

Ultrafast vibrational relaxation dynamics of LDS698 dye molecule in solution are theoretically studied on the basis of the perturbative density operator method and the transient l... [more]

Ultrafast vibrational relaxation dynamics of LDS698 dye molecule in solution are theoretically studied on the basis of the perturbative density operator method and the transient linear susceptibility theory. Femtosecond time-resolved profile on stimulated emission pumping fluoresence depletion is simulated for the system with the single vibrational mode. The vibrational transition rate constant ¿1¿0 is 4.5 ps-1,the two constants C1 and k relating to the solvation are 1.0 and 0.08ps-1 respectively. It is 2.4 for the Huang-Rhy factor S between the first excited S1 state and the ground S0 state. The SEP signal reveals that the fast and the slow decay components reflect the vibrational relaxation and the excited state solvation of the molecule, respectively.

1998 He Y, Xiong Y, Wang Z, Zhu Q, Kong F, 'Theoretical analysis of ultrafast fluorescence depletion of vibrational relaxation of dye molecules in solution', Journal of Physical Chemistry A, 102 4266-4270 (1998)

Ultrafast vibrational relaxation and solvation dynamics of electronically excited dye molecules in solution are theoretically studied on the basis of the perturbative density oper... [more]

Ultrafast vibrational relaxation and solvation dynamics of electronically excited dye molecules in solution are theoretically studied on the basis of the perturbative density operator method and the transient linear susceptibility theory. Femtosecond time-resolved profile of the stimulated emission pumping fluorescence depletion (SEP FD) is simulated with a single vibrational mode. The results show that the fast and the slow SEP components reflect primarily the vibrational relaxation and the solvation effect, respectively, in the first excited state S1 of the dye molecules.

Citations Scopus - 26
1996 Zhong Q, Wang Z, Sun Y, Zhu Q, Kong F, 'Vibrational relaxation of dye molecules in solution studied by femtosecond time-resolved stimulated emission pumping fluorescence depletion', Chemical Physics Letters, 248 277-282 (1996)

A new method, femtosecond time-resolved stimulated emission pumping fluorescence depletion (FS TR SEP FD), has been developed to study the vibrational relaxation of electronic exc... [more]

A new method, femtosecond time-resolved stimulated emission pumping fluorescence depletion (FS TR SEP FD), has been developed to study the vibrational relaxation of electronic excited states of molecules. Two relaxation rates of dye molecules in different solvents have been observed: (i) the intramolecular redistribution of energy, with a short time constant of less than 500 fs; (ii) the subsequent cooling of the vibrationally hot molecules on the picosecond time scale. The rates of these processes strongly depend on the solvent. This may result from a solvent-induced structural modification of the dye molecules.

DOI 10.1016/0009-2614(95)01328-8
Citations Scopus - 49
1996 Zhong Q, Wang Z, Liu Y, Zhu Q, Kong F, 'The ultrafast intramolecular dynamics of phthalocyanine and porphyrin derivatives', Journal of Chemical Physics, 105 5377-5379 (1996)

The internal conversion and intramolecular vibrational relaxation processes of nitro-tri-tert-butylphthalocyanine, tetra-phenylporphyrin (TPP), and tetra-tert-butylphthalocyanine ... [more]

The internal conversion and intramolecular vibrational relaxation processes of nitro-tri-tert-butylphthalocyanine, tetra-phenylporphyrin (TPP), and tetra-tert-butylphthalocyanine (BuPc) in chloroform solution were investigated with an ultrafast time-resolved fluorescence depletion method. A regular fluorescence depletion was observed, indicating that the vibrational relaxation in the S1state takes a few hundred femtoseconds to several picoseconds. For TPP and BuPc, an additional sharp dip superposes on the regular depletion. It is explained by an ultrafast internal conversion process from the S2state to the S1state with a time of a few tens offemtoseconds. © 1996 American Institute of Physics.

DOI 10.1063/1.472378
Citations Scopus - 57
1996 Zhong Q, Wang Z, Zhu Q, Kong F, 'Study of the Ultrafast Processes of TPP, BuPc and NtBuPc', Acta Physico - Chimica Sinica, 12 194-195 (1996)

The ultrafast processes of tetra-phenyl-porphyrin(TPP), tetra-t-butylphthalocyanine(BuPc) and nitro-tri-t-butyl-phthalocyanine (NtBuPc) have been investigated using the femtosecon... [more]

The ultrafast processes of tetra-phenyl-porphyrin(TPP), tetra-t-butylphthalocyanine(BuPc) and nitro-tri-t-butyl-phthalocyanine (NtBuPc) have been investigated using the femtosecond time-resolved fluorescence depletion method. A sharp peak of the fluorescence depletion with delay time has been observed both for TPP and BuPc. An ultrafast two-photon absorption process has been proposed to explain the sharp peak observed. A long-lived fluorescence depletion has also been observed. It is causing by the stimulated-emission-pumping process produced by the intense probe laser pulses.

1996 Zhong Q, Wang Z, Zhu Q, Kong F, 'Femtosecond time-resolved fluorescence depletion technique and its application to study of vibrational relaxation', Progress in Natural Science, 6 441-443 (1996)

A new method, femtosecond time-resolved stimulated emission pumping fluorescence depletion (FS TR-SEP FD), has been developed to study the vibrational relaxation of excited electr... [more]

A new method, femtosecond time-resolved stimulated emission pumping fluorescence depletion (FS TR-SEP FD), has been developed to study the vibrational relaxation of excited electronic state of dye molecules in solution. The relaxation process is a typical biexponential decay: a fast decay within 500 fs (10-15s) followed by a slow decay of 2 ps (10-12s) - 12 ps. The time resolution of 121 fs is limited by the pulse width of our femtosecond laser.

Show 247 more journal articles

Conference (3 outputs)

Year Citation Altmetrics Link
2013 Yang L, Guan C, Yue W, Wu J, Yan H, Zhang X, et al., 'Hybrid molecular nanostructures with donor-acceptor chains', Science China Chemistry (2013)

We have fabricated hybrid molecular chain structures formed by electron acceptor compound 1 and electron donor molecules 2 and 3 at the liquid/solid interface of graphite surface.... [more]

We have fabricated hybrid molecular chain structures formed by electron acceptor compound 1 and electron donor molecules 2 and 3 at the liquid/solid interface of graphite surface. The structural details of the mono-component and the binary assemblies are revealed by high resolution scanning tunneling microscopy (STM). Compound 1 can form two well-ordered lamellar patterns at different concentrations. In the co-adsorption structures, compounds 2 and 3 can insert into the space between molecular chains of compound 1 and form large area well-ordered nanoscale phase separated lamellar structures. The unit cell parameters for the coassemblies can be "flexibly" adjusted to make the electron donors and acceptors perfectly match along the molecular chains. Scanning tunneling spectroscopy (STS) results indicate that the electronic properties of individual molecular donors and acceptors are preserved in the binary self-assembly. These results provide molecular insight into the nanoscale phase separation of organic electron acceptors and donors on surfaces and are helpful for the fabrication of surface supramolecular structures and molecular devices. © 2012 Science China Press and Springer-Verlag Berlin Heidelberg.

DOI 10.1007/s11426-012-4666-y
Citations Scopus - 6
2013 Yuan R, Wang Z, Liu J, 'Application of advanced oxidation processes in treatment of high salinity organic wastewater: Kinetics and AOX formation', ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, New Orleans, LA (2013)
2012 Schemme T, Ditte K, Travkin E, Jiang W, Wang Z, Denz C, 'Perylene bisimide derivatives as innovative sensitizers for photorefractive composites', Proceedings of SPIE - The International Society for Optical Engineering (2012)

In photorefractive composites, we replace the commonly used fullerene derivative phenyl-C61-butyric acid methyl ester (PCBM) by the perylene bisimide dimer DiPBI. In samples, wher... [more]

In photorefractive composites, we replace the commonly used fullerene derivative phenyl-C61-butyric acid methyl ester (PCBM) by the perylene bisimide dimer DiPBI. In samples, wherein poly-n-vinylcarbazole (PVK) is the charge transporting agent and 4-cyano-4-n-pentylbiphenyl (5CB) the nonlinear optical unit, we observe dramatic enhancements in the overall performance of the composites. When we replace PVK by N,N'-diphenyl-N, N'-bis(3- methylphenyl)-[1, 1'-biphenyl]-4, 4'-diamine (TPD) doped polystyrene (PS), the internal photocurrent efficiency is further improved by a factor 11. © 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

DOI 10.1117/12.922671
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Research Collaborations

The map is a representation of a researchers co-authorship with collaborators across the globe. The map displays the number of publications against a country, where there is at least one co-author based in that country. Data is sourced from the University of Newcastle research publication management system (NURO) and may not fully represent the authors complete body of work.

Country Count of Publications
China 245
Australia 34
Germany 30
United States 14
Italy 13
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Dr Zhaohui Wang

Position

Conjoint Senior Lecturer
School of Environmental and Life Sciences
Faculty of Science

Contact Details

Email zhaohui.wang@newcastle.edu.au
Phone (02) 4913 8082
Links Personal Blogs
Google+

Office

Room NIER C 132
Building NIER C.
Location Callaghan
University Drive
Callaghan, NSW 2308
Australia
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