In situ generated highly active copper oxide catalysts for the oxygen evolution reaction at low overpotential in alkaline solutions

Developing efficient water oxidation catalysts made up of earth-abundant elements has attracted much attention as a step toward for future clean energy production. Herein we report a simple one-step method to generate a low cost copper oxide catalyst film in situ from a copper(II) ethylenediamine complex. The resulting catalyst has excellent activity toward the oxygen evolution reaction in alkaline solutions. A catalytic current density of 1.0 mA cm(-2) and 10 mA cm(-2) for the catalyst film requires the overpotentials of only similar to 370 mV and similar to 475 mV in 1.0 M KOH, respectively. This catalytic performance shows that the new catalyst is one of the best Cu-based heterogeneous OER catalysts to date.