Simplified two-electrode electrochemical growth and characterization of Cd1-xZnxS thin films: Influence of electrolytic bath pH

Cd1-xZnxS thin films were prepared from an aqueous electrolytic solution using a simple low-cost two-electrode electrodeposition technique. Effect of pH on physico-chemical properties was studied at three different pH values of 1.8, 2.7 and 3.6. It was found as the pH is raised, intensity of the X-ray diffraction peaks of the films decreased gradually. Raman measurement also showed similar observation a decrease in intensity of peaks as pH is raised. Compositional characterization shows that more Zn is incorporated into the CdS lattice as pH increases and on the other hand deposition rate decreases due to formation of more OH- ions in the bath. SEM measurement reveals that the variation of pH significantly influences surface morphology of the films. The optical band gap ranges from 2.43 eV to 2.50 eV which indicate that, electrodeposited Cd1-xZnxS thin films can be used as good window/buffer layer for solar cell application in place of CdS.