Constructing Ag/CuO Interface for Efficient Neutral CO Electroreduction to CH.

Neutral CO electroreduction to multi-carbons (C) offers a promising pathway to reduce the CO and energy losses originating from the carbonate formation. However, the sluggish kinetics of C-C coupling brings a significant challenge of achieving high selectivity of a single product (such as ethylene), especially at industrial-relevant current densities (>300 mA cm). Here, we reported an optimized Ag-CuO interfacial catalyst that exhibited C Faradaic efficiency (FE) of 73.6 % at 650 mA cm in a flow cell. Remarkably, it obtained FE of 66.0 % with a partial current density of 429.1 mA cm, making it stand out among the reported Cu-based electrocatalysts. In situ Raman spectra uncovered that the Ag/CuO interfaces enabled a high coverage of *CO around the partially reduced Cu/Cu active sites. Furthermore, theoretical calculations demonstrated the enhanced CO formation and C-C coupling at the Ag/CuO interface. This work reported an unprecedented neutral CO electroreduction to CH performance and provided an in-depth comprehension of the role of the bimetallic interface.