Efficient CO 2 Electroreduction to Ethanol by Cu 3 Sn Catalyst.

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.