Electrocatalytic CO 2 Reduction to C 2 Products via Enhanced C─C Coupling Over Cu‐based Catalysts: Dynamic Reaction and Regulation Mechanism

Abstract Benefiting from the optimal interaction strength between Cu and reactants, Cu‐based catalysts exhibit a unique capability of facilitating the formation of various multi‐carbon products in electricity‐driven CO 2 reduction reactions (CO 2 ERR). Nonetheless, the CO 2 ERR process on these catalysts is characterized by intricate polyproton‐electron transfer mechanisms that are frequently hindered by high energy barriers, sluggish reaction kinetics, and low C─C coupling efficiency. This review employs advanced characterization techniques, such as sum frequency generation technology, to provide a comprehensive analysis of the CO 2 ERR mechanism on the Cu surface, examining it from both spatial and temporal dimensions and proposing a spatial‐temporal coupling reaction mechanism. To improve C─C coupling efficiency, a series of regulatory strategies are focused on surface microenvironment, catalyst surface structure, and internal electronic structure, thereby offering novel insights for the upcoming design and enhancement of Cu‐based electrocatalysts.