Growth of Cadmium Sulphide Nanorods Using Chemical Bath Deposition Technique by Varying Cd/S Concentration

Cadmium sulfide (CdS) thin films were prepared using the chemical bath deposition method onto glass substrates at constant reaction temperature of 85 °C. Cadmium sulphate and thiourea were used as sources of Cd+2 and S-2 ions respectively. Films were prepared by varying cadmium concentration (viz. 1, 5 and 10 mM) keeping thiourea concentration constant (20 mM). These films were examined for their structural and surface morphologies by X-ray diffraction analysis (XRD) and atomic force microscopy (AFM). Analysis of results suggests that CdS nanorods grow with cadmium sulphate concentration of 10 mM. The optical properties were investigated using UVVIS spectrophotometer. The values of optical band gaps as-calculated from optical transmission measurements suggests that films have energy band gap in the range of 2.38-2.32eV decreases with increase of cadmium concentration.