Efficient Electrochemical Reduction of CO 2 to C 2 H 4 Over Low Work Function Cu/ZnO Film Catalysts

Abstract Cu‐based catalysts for electrochemical CO 2 reduction reactions facilitate the transformation of CO 2 into economically viable multicarbon products. There remains a pressing need to design efficient, stable, and cost‐effective catalysts to enhance the selectivity for these multicarbon products. Metal‐oxide heterogeneous interface can modify the electronic structure of metal surfaces, influencing the adsorption energy of crucial intermediates and thereby enhancing the selectivity for multicarbon products. In this study, Cu/ZnO electrodes are prepared by magnetron sputtering to achieve a Faraday efficiency of 51.2% for C 2 H 4 at −1.17 V. The Cu/ZnO heterogeneous interface provided abundant active sites for the reaction, and the lower work function facilitated the multi‐electron transfer process necessary for the reduction of CO 2 to C 2 H 4 , thereby enhances the catalytic performance. DFT calculations reveal that the upward shift in the d‐band center of Cu/ZnO, compared to pure Cu, enhances the adsorption energy of the crucial intermediate * CO. Moreover, the C‐C coupling achieved on Cu/ZnO through the * CHO‐ * CHO pathway, which features lower energy barriers, ensures high selectivity in the conversion of CO 2 to C 2 H 4 . This work provides a promising and effective strategy for the large‐scale development of metal‐oxide catalysts for the electrochemical reduction of CO 2 to C 2 H 4 .