The preparation and characterization of CdS_1-xTe_x semiconductor films for hydrogen production by the chemical bath deposition method

Te-doped CdS semiconductor films were fabricated on indiumtinoxide (ITO) substrates by chemical bath deposition. The chemical composition, morphology, crystalline, and optical properties of the Te-doped CdS films were characterized by XPS, SEM, XRD, UVvis, and Ellipsometer. Additionally, the carrier density and flat-band potential of the semiconductor electrodes were measured by Hall and potentiostat. Results show that the electrical property of Te-doped CdS films was changed from n-type to p-type semiconductors, when the molar ratios of Te in the bath solution were higher than 0.4. Besides, energy band-gap and carrier densities of the Te-doped samples were found in the range of 1.852.33 eV and 9.68×10¹⁵1.56×10¹⁷ cm^-3, respectively. Furthermore, the maximum photocurrent density of the samples was found to be -0.81 mA/cm² (under the external potential of -1.0 V) with the largest hydrogen production capability of 1.29 ml/cm², when illuminated under a 150 W Xe lamp.