Photoelectrochemical performance of CuO electrodes by surface modification with ZnO in Water Splitting Process

摘要

Nanostructured CuO thin film photoelectrodes of altering thickness modified by overlayering of ZnO thin films were used in photoelectrochemical (PEC) water splitting. The influence of surface modification, by layering of wide band gap semiconductor over small band gap semiconductor with appropriate thickness, on PEC performance and the stability has been investigated. It was found that modified CuO thin films showed significant enhancement in photocurrent density and photoconversion efficiency and better stability than that of pristine CuO photoelectrodes. Maximum photocurrent 2 density 1.52 mA/cm at -0.8 V/SCE under visible light illumination for CuO/ZnO thin films was observed offering 1.23% photoconversion efficiency. An energy band diagram of CuO/ZnO junction has also been discussed to explore the charge transfer process across the interface.