Structural and optical properties of CdO/ZnS core/shell nanocomposites

XRD pattern of prepared samples confirm the predominant phase is CdO and small, broad peaks show the ZnS phase in nanocomposites. This XRD data is indexed to cubic crystal system and lattice parameter is calculated as a = 4.6916 Å. After the deposition of ZnS, small blue diffraction peaks are observed for cubic CdO nanostructures. The corresponding lattice cell parameters are evaluated as a = 4.6910 for CdO and a = 5.3735 Å for ZnS. After formation of the CdO-ZnS nanocomposites, the peak intensities of CdO decrease and new peaks due to ZnS are observed. This supports the fact that ZnS particles are deposited on the surface of CdO. These results shows well agreement with standard diffraction data of JCPDS file No. 05-0640 for face centred cubic CdO and file No. 05-0566 for cubic ZnS. From this diffraction data crystallite size, strain and dislocation density are evaluated from Scherrer's formula and Williamson and Hall. After the deposition of ZnS, increase in particle size and decrease in strain and dislocation density is observed.