Cu2-xSe@CuO core-shell assembly grew on copper foam for efficient oxygen evolution

Hydrogen production from electrolyzed water is a mature technology and has great development prospects in terms of energy conversion and utilization. However, the kinetically sluggish oxygen-evolution reaction becomes the limiting step in the electrolysis of water . Copper-based materials have been reported as a good choice to catalyze the oxygen evolution reaction , but their performance is poor. We describe a Cu 2-x Se@CuO/copper foam core–shell structure from the in situ electrochemical oxidation of Cu 2 Se/copper foam to promote the oxygen-evolution reaction performance. The presence of a semi-metallic Cu 2-x Se core and nanostructured CuO shell at a current density of 10 mA cm −2 requires a low overpotential of 253 mV. The Tafel slope was only 73 mV dec −1 . The preparation of Cu 2-x Se@CuO on three-dimensional copper foam facilitates the reaction.