PNNL

Abstract

Cd1-xZnxS (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 Cd1-xZnxS are hexagonally oriented and Zn2+ is successfully introduced into CdS. SEM results indicate that high Zn2+ doping concentration can form flake-like Cd1-xZnxS 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. The PEC cell results indicate that the Cd1-xZnxS thin films with x > 0.3 in the bath show the pinning of the Fermi level and cause VOC to decrease.