Photoelectrochemical behaviour of pulse plated CdS films

Cadmium sulphide (CdS) films were deposited by the pulse plating technique at room temperature and at different duty cycles in the range of 6–50% using AR grade 0.25 M cadmium sulphate and 0.30 M sodium thiosulphate at a deposition potential of −0.75 V (SCE). The total deposition time was kept constant at 1 h. The thickness of the films were around 2.0 μm. X-ray diffraction (XRD) studies indicate the formation of polycrystalline films with the cubic structure. The crystallite size increased from 23.0 to 27.5 nm as the duty cycle increased from 10 to 50%. Optical absorption studies indicated a direct band gap in the range of 2.40–2.80 eV as the duty cycle is decreased. XPS studies indicated the formation of CdS. Photoelectrochemical (PEC) cell measurements made with the photoelectrodes deposited at 50% duty cycle have exhibited higher conversion efficiency compared to earlier reports.