Engineering Atom‐Scale Cascade Catalysis via Multi‐Active Site Collaboration for Ampere‐Level CO2 Electroreduction to C2+ Products

Electrochemical reduction of CO2 to value-added multicarbon (C2+) productions offers an attractive route for renewable energy storage and CO2 utilization, but it remains challenging to achieve high C2+ selectivity at industrial-level current density. Herein, a Mo1Cu single-atom alloy (SAA) catalyst is reported that displays a remarkable C2+ Faradaic efficiency of 86.4% under 0.80 A cm-2. Furthermore, the C2+ partial current density over Mo1Cu reaches 1.33 A cm-2 with a Faradaic efficiency surpasses 74.3%. The combination of operando spectroscopy and density functional theory (DFT) indicates the as-prepared Mo1Cu SAA catalyst enables atom-scale cascade catalysis via multi-active site collaboration. The introduced Mo sites promote the H2O dissociation to fabricate active *H, meanwhile, the Cu sites (Cu0) far from Mo atom are active sites for the CO2 activation toward CO. Further, CO and *H are captured by the adjacent Cu sites (Cu&+) near Mo atom, accelerating CO conversion and C─C coupling process. Our findings benefit the design of tandem electrocatalysts at atomic scale for transforming CO2 to multicarbon products under a high conversion rate.