In-situ growth of CuCoZn metallic inclusions via surface alloying for enhanced water oxidation at amperometric current densities

Abstract

There is a substantial demand for low-cost, efficient, and stable oxygen evolution reaction (OER) catalysts capable of operating at amperometric current densities green hydrogen production, which is crucial for the future transformation of the energy structure. In this study, OER catalysts (V_Zn-Co@Cu₂S) featuring with Zn ionic vacancies were synthesized via the introduction of guest elements surface alloying technique. Electrochemical tests have demonstrated that the electrochemical OER process involves the surface reconstruction to expose the practical positive active substance (MOOH), with Zn as a sacrificial cation, effectively prevents the overoxidation of the surface metal thereby significantly enhances the catalytic performance. Under the synergistic effect of Cu, Co, and Zn metals, catalyst V_Zn-Co@Cu₂S showed remarkable OER performance, achieving an overpotential of only 360 mV at a current density of 1000 mA cm⁻². Furthermore, it retained over 97.7 % of its initial performance after 100 h of stability testing. The results indicate that V_Zn-Co@Cu₂S holds significant potential for industrial applications and provide valuable insights into the design and development of high-performance OER catalysts.