Steering electrochemical carbon dioxide reduction to alcohol production on Cu step sites

Electrochemical CO₂ reduction is a sustainable method for producing multicarbon alcohols. However, the selectivity of alcohols is limited owing to the favorable side reaction to convert the key intermediate of *CH₂CHO into ethylene. This study describes the design of a Cu electrocatalyst with abundant step sites to suppress the deoxygenation of *CH₂CHO to ethylene, thereby promoting alcohol production. A Faradic efficiency of 40.5% and partial current density of 56.3 mA/cm² for alcohols are achieved. Moreover, the alcohols/C₂H₄ ratio in the products reaches approximately 2.2. In-situ infrared spectrum characterizations and theoretical calculations reveal that the step sites facilitate C–C coupling and direct the reaction pathway to promote the formation of alcohols by inhibiting the cleavage of the C–O bond in *CH₂CHO. Therefore, the proposed strategy is efficient for designing active sites to steer reaction pathways in CO₂ electroreductions and produce alcohols.