Efficient electrochemical CO2 reduction via CuAg doped CeO2

CO2 electrocatalysis reduction (CO2RR) is considered to be one of the most efficient methods to achieve carbon neutralization and realize renewable energy conversion. Unfortunately, at present, CO2 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 CO2RR 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/CeO2-6 catalysts by the simple impregnation method for CO2RR, exhibiting the highest FECO 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 CeO2 support. This effect results in the electronic structure change and the formation of the highest concentration of oxygen vacancies, promoting the CO2 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 CO2RR and the smallest charge resistance of CuAg/ CeO2-6 also contributes to its good CO2RR performance. This work sheds light on the design of other efficient CO2RR catalysts through electronic structure tuning by bimetallic strategy.

Automated summary

In this paper, bimetallic CuAg/CeO2-6 catalysts were designed for CO2RR, showing the highest FECO of 84% at -1.1 V vs. RHE. The electron delocalization effect between Cu and Ag bimetals as well as CeO2 support played a significant role in promoting CO2 adsorption and activation. The design of efficient CO2RR catalysts through electronic structure tuning by bimetallic strategy was proposed.