Structured Cupric Oxide Grown on Copper Sheet as an Effective Electrocatalyst Towards Hydrogen Peroxide Reduction Reaction

Abstract

In this work, a highly efficient and cost-effective electrode material based on a cupric oxide (CuO) thin film was synthesized, and its electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2) was investigated. The CuO film was formed on a copper (Cu) sheet using a direct electrochemical oxidation method in an alkaline medium (4–6 M KOH). This approach enabled the superficial oxidation of the Cu sheet, resulting in the formation of an oxidized layer on its surface. X-ray diffraction (XRD) analysis confirmed the formation of a high-purity CuO film with remarkable crystallinity. Scanning electron microscopy (SEM) revealed that the film possesses a highly rough surface and a homogeneous microstructure. The electrocatalytic performance of the CuO/Cu electrode for the H2O2 reduction reaction was studied in 0.1 M KOH electrolyte using cyclic voltammetry and chronoamperometry techniques. Optimization of the synthesis process showed that the concentration of the KOH electrolyte is critical for the growth of the CuO film and the activity of the catalyst. The effects of H2O2 concentration and potential scan rate on the electrode response were also examined. Under optimized conditions, the CuO/Cu catalyst exhibited excellent performance, displaying an extremely high cathodic overpotential of –0.4 V at a broad reduction current density. Additionally, the electrode demonstrated significant electrochemical stability after prolonged reduction testing. These results suggest that the CuO/Cu electrode has the potential to be an effective cathode electrocatalyst for applications in fuel cells utilizing H2O2 as an oxidant.