Hierarchical Urchin-like Cobalt-Doped CuO for Enhanced Electrocatalytic Oxygen Evolution Reaction

Designing an efficient, low-cost, and earth-abundant electrocatalyst for water oxidation is the center of attraction in renewable energy technology, but it is still a grand challenge. Herein, we report a simple microwave-assisted solvothermal method to synthesize cobalt-doped CuO as a noble metal-free efficient electrocatalyst for oxygen evolution reaction (OER) in an alkaline medium. Optimal cobalt doping (5%) in CuO manifests an improved OER activity with an overpotential of 120 mV, which is similar to 2.66 times lower than that obtained with pristine CuO to achieve a current density of 10 mA cm(-2), superior to the state-of-the-art OER catalysts. A Tafel slope of 118 mV dec(-1) with an electrochemical active surface area of 40 cm(2) and a charge transfer resistance of 2.58 Omega were achieved with 5% cobalt-doped CuO, which validate the role of metal doping and importance of doping in transition metal oxides to enhance the electrochemical OER activity.

Automated summary

A simple microwave-assisted solvothermal method was reported to synthesize cobalt-doped CuO as an efficient electrocatalyst for the oxygen evolution reaction (OER) in an alkaline medium. The optimal cobalt doping showed improved OER activity, highlighting the importance of metal doping in enhancing electrochemical performance.