Active copper delafossite anode for oxygen evolution reaction

The design of highly active anode catalysts for water electrolysis is a critical challenge to achieve a sustainable energy-powered economy. Here we report on copper delafossite oxide (ABO(2); A = Cu) as a novel anode for the oxygen evolution reaction (OER). Among the copper delafossites we synthesized, copper rhodium delafossite (CuRhO2) showed excellent cyclic voltammogram (CV) characteristics for OER in 1 M KOH (aq), comparable to that of Co3O4. We also confirmed that the e(g) orbital occupancy at the B site of delafossites, calculated from the bulk structure, had a strong correlation with the electrochemical OER activity of those materials. The CV characteristics of Cu delafossites were more accurately explained by considering the electronic conductivity. (C) 2013 Elsevier B.V. All rights reserved.