Study on CdS Nanoparticles and Nanocrystalline Thin Films Synthesized by Chemical Bath Deposition Technique

Abstract

Cadmium Sulfide (CdS) nanoparticles and nanocrystalline thin films were synthesized by chemical bath deposition technique at room temperature. The elemental composition of the as-grown CdS nanoparticles and nanocrystalline thin films were determined by energy dispersive analysis of X-rays (EDAX). Crystallite size and lattice parameter were determined from X-ray diffractogram whereas transmission electron microscopy (TEM) image gave particle size and the selected area electron diffraction ring pattern showed the polycrystalline nature of these samples. The UV-VIS-NIR spectra indicated blue shift relative to the bulk form of the material. The Raman spectrum revealed two peaks which correspond to the longitudinal optical phonon mode at frequency 295.25 cm^− 1 and 600 cm^− 1 for CdS nanoparticles and at frequency 304.31 cm⁻¹ and 550 cm^− 1 for thin film indicating good agreement with earlier reported results. An extra peak centered at 207.81 cm^− 1and 406.16 cm^− 1for CdS nanoparticles and thin films respectively corresponds to the surface phonon mode. Thermogravimetric analysis (TGA) carried out on CdS nanoparticles revealed that the nanoparticles are thermally stable between 50 º C to 600 º C and above 600 º C they start decomposing.

Keywords:  Nanoparticles, nanocrystalline thin films, semiconductor materials