Optical, structural and photo electrochemical properties of Cd_1-xZn_xS films grown by chemical bath deposition

Cd_1-xZn_xS (0 ≤ x ≤ 0.5) films were fabricated by chemical bath deposition method and characterized by grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), UV-visible spectroscopy and photoelectrochemical (PEC) cell. The flat-band potential value was found to be tunable from -441 to -664 mV with increasing Zn²⁺ concentration in the reaction solution. GIXRD results indicate that the fabricated Cd_1-xZn_xS are hexagonally oriented and Zn²⁺ is successfully introduced into CdS. SEM results indicate that high Zn²⁺ doping concentration can form flake-like Cd_1-xZn_xS morphology. Furthermore, Zn²⁺ incorporation to the CdS was found to enhance the optical absorbing capability of CdS in visible region. The optical band gap was found to vary as the composition parameter changed from x = 0.0 to x = 0.5 in the reaction solution. Best photoactive properties in the PEC exhibited for the samples grown with the deposition bath composition of x = 0.3. (orig.)