Engineering Surface Oxophilicity of Copper for Electrochemical CO Reduction to Ethanol.

Copper-based materials are known for converting CO into deep reduction products via electrochemical reduction reaction (CO RR). As the major multicarbon products (C ), ethanol (C H OH) and ethylene (C H ) are believed to share a common oxygenic intermediate according to theoretical studies, while the key factors that bifurcate C H OH and C H pathways on Cu-based catalysts are not fully understood. Here, a surface oxophilicity regulation strategy to enhance C H OH production in CO RR is proposed, demonstrated by a Cu-Sn bimetallic system. Compared with bare Cu catalyst, the Cu-Sn bimetallic catalysts show improved C H OH but suppressed C H selectivity. The experimental results and theoretical calculations demonstrate that the surface oxophilicity of Cu-Sn catalysts plays an important role in steering the protonation of the key oxygenic intermediate and guides the reaction pathways to C H OH. This study provides new insights into the electrocatalyst design for enhanced production of oxygenic products from CO RR by engineering the surface oxophilicity of copper-based catalysts.