Efficient Electrocatalytic Water Oxidation by a Copper Oxide Thin Film in Borate Buffer

Abstract

A robust water oxidation catalyst based on copper oxide was prepared by facile electrodeposition of Cu 2+ from borate buffer solution under near neutral conditions. The Cu–B i thin film exhibits high activity and long-term stability in Cu 2+ -free pH 9 borate buffer. A steady current density of 1.2 mA/cm 2 was sustained for at least 10 h at 1.3 V versus NHE without iR compensation, which sets a new benchmark for copper-based OEC.