Synergistic mechanism of ECO2RR to ethanol on electrodeposited bimetallic CuAg catalyst

Electrochemical carbon dioxide reduction reactions (ECO 2 RR) for ethanol synthesis represents a highly valuable yet challenging objective, mainly due to the low selectivity and elusive formation mechanism. This study aims to address this challenge by designing a pulsed-electrodeposited bimetallic CuAg catalyst. The surface morphology and elemental valence state distribution of the CuAg catalyst were comprehensively characterized using BET/SEM/EDS/XRD/XPS techniques. Subsequently, the electrocatalytic performance was systematically investigated based on CV/LSV/EIS/GC/ 1 H NMR methods. The results indicated that the CuAg catalyst attained a Faradaic efficiency of 11.39 % for ethanol production at a current density of 84 mA·cm −2 , along with an ethanol/ethylene selectivity of 8.26. In combination with the analysis of DFT calculations, the incorporation of Ag into the Cu catalyst enhanced the catalytic performance primarily through three mechanisms: increasing the specific surface area and porosity to generate more Cu active sites and high ESCA , modifying the electronic structure of Cu atoms to facilitate the C–C coupling pathway, and reducing the interfacial resistance to promote reaction kinetic rates. These findings provide atomic-level insights into the ECO 2 RR mechanism and establish a novel paradigm for the design of bimetallic catalysts to achieve the efficient synthesis of multi-carbon fuels such as ethanol.