Thermally Induced Morphological and Structural Transitions of Zinc Blende CdSe Hollow Nanoparticles Studied by Molecular Dynamics Simulation

摘要

The morphological and structural transitions in CdSe hollow nanoparticles (hNPs) with zinc blende structure have studied by molecular dynamics (MD) simulation method under heating. The seven samples of CdSe-hNPs are constructed with different thicknesses from the solid NPs at lOnm and 15nm sizes. Morphological changes in CdSe-hNPs have presented by describing the first stage melting in hollow semiconductor NPs. The thermal effect on the atomic arrangement has also examined by the cubic zinc blende-to-wurtzite transformation occurred during the melting in hNPs. MD results show that the inner shells of those with thin walls have begun to melt at lower temperatures due to the thickness of the NPs. The first stage melting, which resulted in the filling of the void within the particle, takes place almost at the same temperature for hNPs with the thick wall thickness. Then, the melting of the particles is completed at higher temperatures. The cubic diamond structure disappears with the collapse of the inner cavity, and the hep structure begins to appear at later temperatures.