Efficient electrocatalytic reduction of carbon dioxide to ethylene on copper–antimony bimetallic alloy catalyst

The exploration of efficient electrocatalysts for the reduction of CO₂ to C₂H₄ is of significant importance but is also a challenging subject. Cu-based bimetallic catalysts are extremely promising for efficient CO₂ reduction. In this work, we synthesize a series of porous bimetallic Cu–Sb alloys with different compositions for the catalytic reduction of CO₂ to C₂H₄. It is demonstrated that the alloy catalysts are much more efficient than the pure Cu catalyst. The performance of the alloy catalysts depended strongly on the composition. Further, the alloy with a Cu:Sb ratio of 10:1 yielded the best results; it exhibited a high C₂H₄ Faradaic efficiency of 49.7% and a high current density of 28.5 mA cm⁻² at −1.19 V vs. a reversible hydrogen electrode (RHE) in 0.1 M KCl solution. To the best of our knowledge, the electrocatalytic reduction of CO₂ to C₂H₄ using Cu–Sb alloys as catalysts has not been reported. The excellent performance of the porous alloy catalyst is attributed to its favorable electronic configuration, large surface area, high CO₂ adsorption rate, and fast charge transfer rate.