Ceo2/Cus Nanoplates Electroreduce Co2 to Ethanol with Stabilized Cu+ Species

Abstract Copper‐based electrocatalysts effectively produce multicarbon (C 2+ ) compounds during the electrochemical CO 2 reduction (CO 2 RR). However, big challenges still remain because of the chemically unstable active sites. Here, cerium is used as a self‐sacrificing agent to stabilize the Cu + of CuS, due to the facile Ce 3+ /Ce 4+ redox. CeO 2 ‐modified CuS nanoplates achieve high ethanol selectivity, with FE up to 54% and FE C2+ ≈ 75% in a flow cell. Moreover, in situ Raman spectroscopy and in situ Fourier‐transform infrared spectroscopy indicate that the stable Cu + species promote CC coupling step under CO 2 RR. Density functional theory calculations further reveal that the stronger * CO adsorption and lower CC coupling energy, which is conducive to the selective generation of ethanol products. This work provides a facile strategy to convert CO 2 into ethanol by retaining Cu + species.