Synergistic Effects in the Electrochemical Carbon Dioxide Reduction Reaction for Multi‐Carbon Product Formation

Abstract The synergistic effects in electrocatalysis can significantly enhance catalyst performance by improving catalytic activity, selectivity, and stability, and optimizing reaction mechanisms and electron transfer processes. This review summarizes recent advancements in the synergistic effects of the electrochemical reduction of CO ₂ (eCO ₂ RR) to multi‐carbon (C ₂₊ ) products. Starting with the fundamental principles of eCO ₂ RR for C ₂₊ product formation, the paper outlines the reaction mechanisms for producing C ₂ , C ₃ , C ₄ , and C ₅ products. A comprehensive discussion is provided on the critical impact of synergistic effects on the structure–performance relationship in eCO ₂ RR for the production of C ₂₊ products. Subsequently, the synergistic effects observed are classified in various electrocatalysts with different properties, including single/dual‐atom catalysts, multi‐centric catalysts, single‐atom alloys, metal‐organic frameworks, and heterojunction catalysts. Finally, the challenges in achieving selective C ₂₊ product formation in eCO ₂ RR through synergistic effects are discussed, along with corresponding strategies to overcome the obstacles.