Selective CO Electroreduction to Multicarbon Oxygenates Over Atomically Dispersed Cu-Ag Sites in Alkaline Membrane...

Electrochemical carbon monoxide reduction reaction (CORR) to produce multicarbon (C₂₊) oxygenates using renewable electricity is a promising carbon utilization pathway. However, the performance of this process suffers from low C₂₊ oxygenates selectivity and insufficient current density. Here, we employed a Cu-Ag bimetallic strategy to enhance the selectivity of C₂₊ oxygenates from CORR in alkaline membrane electrode assembly electrolyzer at ampere-level current densities. The Cu-Ag catalysts prepared by magnetron sputtering feature atomically dispersed Cu-Ag sites on the catalyst surface, which are key to promoting the formation of C₂₊ oxygenates. Increasing Ag content favors C₂₊ oxygenates formation while inhibiting ethylene production. The optimized Cu₂Ag catalyst achieved Faradaic efficiency of 71.4% for C₂₊ oxygenates at 2.5 A cm^-2. In situ spectroscopy and density functional theory calculations revealed that atomically dispersed Cu-Ag sites on the catalyst surface promote the dissociation of *COCOH to *CCO, thus favoring C₂₊ oxygenates formation.