Efficient CO2 Electroreduction to Ethanol by Cu3Sn Catalyst

Abstract Electrochemical carbon dioxide reduction to ethanol suggests a potential strategy to reduce the CO 2 level and generate valuable liquid fuels, while the development of low‐cost catalysts with high activity and selectivity remains a major challenge. In this work, a bimetallic, low‐entropy state Cu 3 Sn catalyst featuring efficient electrocatalytic CO 2 reduction to ethanol is developed. This low‐entropy state Cu 3 Sn catalyst allows a high Faradaic efficiency of 64% for ethanol production, distinctively from the high‐entropy state Cu 6 Sn 5 catalyst with the main selectivity toward producing formate. At an industry‐level current density of −900 mA cm −2 , the Cu 3 Sn catalyst exhibited excellent stability for over 48 h in a membrane‐electrode based electrolyzer. Theoretical calculations indicate that the high ethanol selectivity on Cu 3 Sn is attributed to its enhanced adsorption of several key intermediates in the ethanol production pathway. Moreover, the life‐cycle assessment reveals that using the Cu 3 Sn electrocatalyst, an electrochemical CO 2 ‐to‐ethanol electrolysis system powered by wind electricity can lead to a global warming potential of 120 kg CO2‐eq for producing 1 ton of ethanol, corresponding to a 55% reduction of carbon emissions compared to the conventional bio‐ethanol process.