Boosting carbon monoxide production during CO₂ reduction reaction via Cu-Sb₂O₃ interface cooperation

Development of multiple-component catalyst materials is a new trend in electrochemical CO₂ reduction reaction (eCO₂RR). A new type of metal-oxide interaction is reported here to improve carbon monoxide production via synergistic effect between the CO₂-to hydrocarbon selective metal material and CO₂-to hydrogen generation oxide material. Cu/Sb₂O₃ material originates from the hetero-structured CuO/Sb₂O₃ by a facile two-step hydrolysis and precipitation method, cooperative to inhibit hydrogen evolution or methane product, achieving CO Faradaic efficiency to 92% in CO₂ saturated KCl electrolyte at -0.99 V with good stability. The formation of a stable *COOH intermediate by electronic and geometric effects via Cu and Sb₂O₃ are responsible to promote CO selectivity. Cu-Sb₂O₃ interface interaction also destabilizes the adsorption *H as well, an intermediate for H₂ evolution. This study proposes a versatile design strategy for construction and utilization of metal-oxide interface for eCO₂RR.