Mg-doped CdS thin film deposition and characterization by simplified twoelectrode electrodeposition method: effect of electrolytic bath pH

Abstract Mg-doped CdS thin films were successfully grown on ITO glass substrate using the electrodeposition system. Electrolytic bath pH of 1.8, 2.3, 2.8, and 3.3 were used for the deposition process. The energy dispersive x-ray spectroscopy, room-temperature photoluminescence (PL), scanning electron spectroscopy, UV–vis spectrophotometry, and x-ray diffraction were the methods used to scrutinise the structural, optical, morphological, photoluminescence, and compositional properties of these produced thin films using a two-electrode setup. The results show that a film’s structural, optical, and morphological properties are strongly influenced by electrolytic bath pH at which it is deposited. As the pH of the electrolytic solution decreased, the CdS: Mg thin film’s crystallinity improved. The electrolytic bath pH drops from 3.3 to 1.8, resulting in a drop in energy band gap film from 3.44 to 2.40 eV. As the electrolytic bath pH rises, the elemental composition of Mg gradually increased resulting in high transmittance.