One-Step Electrodeposition of Cu-Sn Alloy Catalysts for Efficient Electroreduction of CO2 to Formate
Electrocatalytic CO2 reduction reaction (CO2RR) offers a promising route to mitigate CO2 emissions while producing valuable chemicals. This study reports a Cu-Sn alloy catalyst with a wheat-ear-like dendritic structure, fabricated via a one-step electrodeposition method, for selective CO2 electroreduction to formate. Compared to pure Cu and Sn electrodes, the Cu-Sn alloy exhibits superior catalytic activity and selectivity toward formate, achieving a maximum Faradaic efficiency (FE) of 80% and maintaining above 70% FE over a potential window from -1.7 V to -2.0 V (vs. Ag/AgCl). The enhanced performance is attributed to the unique dendritic morphology that provides abundant active sites and the synergistic alloying effect that modulates the adsorption of the CO2*- intermediate, as corroborated by electrochemical measurements and X-ray photoelectron spectroscopy (XPS). This work presents a facile strategy for designing bimetallic catalysts for efficient CO2RR to formate.