1 research outputs found
Shape-Controlled CdS/ZnS Core/Shell Heterostructured Nanocrystals: Synthesis, Characterization, and Periodic DFT Calculations
CdS/ZnS core/shell heterostructured
nanocrystals (NCs) with six
monolayers (MLs) of ZnS shell on a zinc-blende CdS core were synthesized
via successive ionic layer adsorption and reaction. By adjusting the
growth temperature of the ZnS shell from 220 to 280 °C, the shape
of CdS/ZnS NCs can be tuned to tetrapods, tetrahedra, and dots. Shell
growth was confirmed to be uniform by X-ray diffraction, transmission
electron microscopy, UV–vis absorption, and photoluminescence
spectroscopy. Periodic density functional theory calculations were
used to further study the growth mechanism of the differently shaped
CdS/ZnS core/shell NCs. Our calculations revealed that the binding
energy of model CH<sub>3</sub>CH<sub>2</sub>NH<sub>2</sub> molecules
on the (110), (111), and (001) facets of the CdS core can determine
which crystallographic facets are favored during the growth of the
ZnS shell. The calculations provided insights into the effect of the
interaction between the organic ligand and the facets of the CdS core
on the shape engineering of CdS/ZnS core/shell NCs