Potentiostatic electrodeposition of Cu2O under light and dark for photoelectrochemical hydrogen generation applications

Abstract

Potentiostatic electrodeposition conducted at various deposition voltages from lactate-stabilized copper sulfate electrolyte was used for preparation of Cu2O layers for Photoelectrochemical (PEC) production of hydrogen. A novel approach based on an application of light during the electrodeposition is utilized to suppress the potential drop in the Cu2O layer during the potentiostatic deposition. Structures prepared under dark and light on an Ag substrate are analyzed by X-Ray Diffraction analysis (XRD), Scanning Electron Microscopy (SEM) and Linear Sweep Voltammetry (LSV). It was shown that the application of light increases the deposition rate due to the contribution of the photogenerated carriers. The deposition voltage affects the photoresponse of light deposited structures but causes only a negligible change in dark deposited structures. The light deposited samples exhibited a higher photoresponse for all deposition voltages. The presented study suggests the light potentiostatic electrodeposition as an attractive approach for the preparation of Cu2O structures for cheap and efficient photoelectrochemical water splitting applications.