CuAg bimetallic catalysts derived from an Ag-anchored Cu-based metal–organic framework for CO2 electroreduction to ethanol

Constructing a bimetallic tandem catalytic system is an effective strategy to promote the CO 2 electroreduction (CO 2 ER) to ethanol. However, it is still difficult to achieve high selectivity for ethanol in the CO 2 ER because most of bimetallic catalysts lack sufficient biphasic boundaries. Herein, a series of novel CuAg bimetallic catalysts (CuAg x @NC) were prepared by anchoring Ag in the Cu-based metal–organic framework (NH 2 -Cu-BDC) followed with high-temperature pyrolysis. The results showed that the Ag in the optimal CuAg 5 @NC catalyst was highly dispersed and anchored on the Cu surface, so the catalyst had sufficient Cu-Ag biphasic boundaries, which resulted in superior C 2 products (especially ethanol) selectivities in the CO 2 ER: the Faradaic efficiency (FE) for ethanol production reached 51.8 % at − 1.0 V, and the FE for total C 2 products reached 82.6 % at − 1.2 V, which were higher than those of most previously reported CuAg electrocatalysts. Analyses of the reaction mechanism showed that the appropriate amount of Ag in the NH 2 -Cu-BDC derivative improved the CO coverage on the catalyst surface, promoted C-C coupling and enhanced the adsorption of key intermediates (such as CH 3 CHO) in the ethanol pathway.