Effect pH on Structural and Optical Properties of Nanostructure CdS Films Prepared by Chemical Bath Deposition Technique

Nanostructures CdS films were prepared by chemical bath deposition technique on glass substrates, where the cadmium nitrate salt was used as a source of cadmium ions and thiourea (SC(NH2)2) as a source of sulphide ions(S-2). The deposition were carried out at different pH values. Structure of these films was characterized by X-ray diffraction and atomic force microscope (AFM). CdS films deposited have cubic(zinc blende) structure and the grain size of nanoclusters decreases with increasing pH value in solution. The optical properties study by transmission spectra and the films have highly transmittance in visible region of spectrum and reach to more than 86%. The CdS films have band gap increase from 2.42 to 2.58 eV with increasing pH value in solution