Photoelectrochemical properties of electrochemically deposited metal chalcogenide/ZnO films

In this work we studied metal chalcogenide sensitization of ZnO by electrochemical deposition which provides a fine electric contact between metal sulfide and the oxide. Deposition conditions to prepare the CdS/ZnO and Ag2S/ZnO films with optimized photoelectrochemical (PEC) properties are investigated. Effect of deposition technique, time, Mn-doping and post-annealing on photoresponse of the fabricated films are discussed. A short circuit current density of 1.42 mA/cm2 and an open circuit potential of −1.39 V (overall power conversion efficiency of 0.81%) have been achieved for the annealed Mn-doped CdS/ZnO electrode which is prepared by potensiostatic deposition. Potensiostatic deposition yields Ag2S in Acanthite form which is accompanied by ZnO degradation and the photoelectrode exhibits considerably enhanced and widened light absorption but lower overall power-conversion efficiency.