Hollow nanostructures are of great interest as vehicles for drug delivery, as nano-reactors for gas phase reactions and for their unique optical, magnetic and electronic properties. In this research, making use of molecular dynamics simulation we are investigating the formation of hollow nano-objects by tailored interdiffusion of coated nanospheres, see Figure 1. Since hollow nano-objects are, in principle, thermodynamically unstable, we are making use of Monte Carlo and molecular dynamics methods to investigate shrinkage mechanisms of various hollow nano-objects by diffusion.
Figure 1. Snapshot of a Ni-Pd nanocrystal showing a Ni subsurface shell having a structure of the Kagomé net with 'sequence faults' after ~ 0.3 ms of annealing at T = 1000 K. Every Ni atom of the subsurface shell is located in the centres of interpenetrating icosahedra and almost always has 4 Ni and 8 Pd nearest neighbours.