Structural and optical characteristics of nanoparticles of zinc oxide based ternary compounds generated by simple sol-gel technique.

Abstract

A simple sol-gel process was employed to synthesize Zn1-xCdxO (x = 0, 0.02, 0.04, 0.06) nanoparticles. The powders have a Hexagonal Wurtzite phase, according to X-ray diffraction investigations. The findings of Rietveld refinement fitting revealed a considerable shift in the lattice parameters of Zn1-xCdxO compounds with increasing cadmium content. The average crystallite size of undoped ZnO, Zn0.98Cd0.02O, Zn0.96Cd0.04O, and Zn0.94Cd0.06O compounds was determined using Scherrer formula to be 41.58 nm, 38.05 nm, 37.92 nm, and 39.52 nm, respectively. SEM micrographs exhibit needle-like features in cadmium doped ZnO compounds, but not in undoped ZnO compounds. These micrographs also reveal that the nanostructures have a random size distribution and become more agglomerated as the cadmium concentration rises. The optical band gap, as determined by Ultraviolet-Visible Spectroscopy, decreased from 3.22 to 3.15 eV as cadmium content increased. The photoluminescence spectrum recorded at room temperature by 310 nm excitation wavelength. PL spectra exhibited three different emission bands around 410 nm, 460 nm and 510 nm. The broadness of strong green emission peak was observed to increase with cadmium concentration. All the luminescence peaks are explained as due to various defects like zinc vacancy, oxygen vacancy, zinc interstitial and their complexes.