Sputtering induced the architecture of “needle mushroom” shaped Cu2O–NiCo2O4 heterostructure with novel morphology and abundant interface for high-efficiency electrochemical water oxidation

Abstract

Oxygen evolution reaction (OER) is widely recognized as a bottleneck in the kinetics and activity of decomposition water. Unique geometric design and compositional regulation are important technologies for achieving significant activity and excellent kinetics, but they continue to face obstacles in reaction thermodynamics and kinetic response. Here, a “needle mushroom” shaped Cu2O–NiCo2O4 heterostructure with abundant active sites and optimized conductivity that is grown on the Nickel-foam (NF) (labeled as Cu2O–NiCo2O4/NF-2) is prepared using advanced magnetron sputtering strategies for electrochemical water oxidation. Based on the excellent geometric advantages and efficient charge transfer capabilities, the catalyst of Cu2O–NiCo2O4/NF-2 shows superior electrocatalytic activity (low overpotential) and kinetics (low electrochemical impedance) compared with nanoneedle shaped Cu2O–NiCo2O4/NF-1 and NiCo2O4/NF for OER in alkaline medium. This work demonstrates a practical and economical strategy toward the fabrication of ternary transition metal oxides for water oxidation.