Efficient electrochemical CO2 reduction via CuAg doped CeO2

CO 2 electrocatalysis reduction (CO 2 RR) is considered to be one of the most efficient methods to achieve carbon neutralization and realize renewable energy conversion. Unfortunately, at present, CO 2 electrocatalysts confront the challenges of high overpotential, low selectivity, and poor stability. Ag based electrocatalysts are considered to be the most promising catalysts for CO production via CO 2 RR on a large scale, due to their relatively higher catalytic performance and more abundant reserves compared with other noble metals. Whereas, they still suffer from high cost. In this paper, we design bimetallic CuAg/CeO 2 -6 catalysts by the simple impregnation method for CO 2 RR, exhibiting the highest FE CO of 84% at –1.1 V vs. RHE compared with other bimetallic catalysts with different Cu/Ag ratio and monometal catalysts. XPS results demonstrate the electron delocalization effect not only between Cu and Ag bimetals but also among CeO 2 support. This effect results in the electronic structure change and the formation of the highest concentration of oxygen vacancies, promoting the CO 2 adsorption and activation as well as facilitating the formation of COOH* intermediates as evidenced by the in situ ATR-SEIRAS measurements. Additionally, the highest active surface for CO 2 RR and the smallest charge resistance of CuAg/CeO 2 -6 also contributes to its good CO 2 RR performance. This work sheds light on the design of other efficient CO 2 RR catalysts through electronic structure tuning by bimetallic strategy.