Cascade Dual Sites Modulate Local CO Coverage and Hydrogen-Binding Strength to Boost CO2 Electroreduction to Ethylene

Rationally modulating the binding strength of reaction intermediates on surface sites of copper-based catalysts could facilitate C–C coupling to generate multicarbon products in an electrochemical CO 2 reduction reaction. Herein, theoretical calculations reveal that cascade Ag–Cu dual sites could synergistically increase local CO coverage and lower the kinetic barrier for CO protonation, leading to enhanced asymmetric C–C coupling to generate C 2 H 4 . As a proof of concept, the Cu 3 N-Ag nanocubes (NCs) with Ag located in partial Cu sites and a Cu 3 N unit center are successfully synthesized. The Faraday efficiency and partial current density of C 2 H 4 over Cu 3 N-Ag NCs are 7.8 and 9.0 times those of Cu 3 N NCs, respectively. In situ spectroscopies combined with theoretical calculations confirm that Ag sites produce CO and Cu sites promote asymmetric C–C coupling to *COCHO, significantly enhancing the generation of C 2 H 4 . Our work provides new insights into the cascade catalysis strategy at the atomic scale for boosting CO 2 to multicarbon products.