Synergistic interface engineering in Bi2O3–In2O3@CuO nanowires for highly selective electrocatalytic CO2 reduction to formate

Abstract

Converting carbon dioxide and water into high-value chemicals using renewable energy sources such as solar and wind power is an effective strategy to simultaneously address the depletion of fossil energy and promote low-carbon emissions and alleviate the greenhouse effect. The electrocatalytic carbon dioxide reduction reaction (CO₂RR) involves a multi-proton-coupled electron transfer process comprising multiple steps, including CO₂ adsorption, activation and hydrogenation. Although significant progress has been made in the electrocatalytic reduction of CO₂ to formate, achieving formate production that combines sustained high activity, selectivity and stability still faces severe challenges. This study developed a high-performance electrocatalyst, Bi₂O₃–In₂O₃@CuO, which was obtained by in situ growth of core–shell nanowire structures on Cu foam. In this structure, Cu nanowires acted as the core, and the outer layer was the bismuth–indium metal oxide shell. The obtained catalyst exhibited excellent performance in the CO₂RR, with a current density reaching 28.4 mA cm⁻² and a Faraday efficiency of formate as high as 88.7%.