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

Abstract

AbstractCopper‐based electrocatalysts effectively produce multicarbon (C2+) compounds during the electrochemical CO2 reduction (CO2RR). 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 Ce3+/Ce4+ redox. CeO2‐modified CuS nanoplates achieve high ethanol selectivity, with FE up to 54% and FEC2+ ≈ 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 CO2RR. 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 CO2 into ethanol by retaining Cu+ species.