Molecule Engineering on Copper‐Based Electrocatalyst Toward Electrocatalytic C─N Coupling for Urea Synthesis

Abstract Electrocatalytic C─N coupling is an emerging process that enables the efficient conversion of CO ₂ and nitrogenous species (e.g., NO _x ) into high‐value products such as urea. Among electrocatalysts, copper (Cu) exhibits promising activity under reduction conditions. However, Cu‐based catalysts often undergo reconstruction during operation, leading to a broad product distribution and poor selectivity toward specific target molecules. Herein, a molecular engineering strategy to enhance the structural stability of Cu‐based catalysts during electrocatalytic C─N coupling is employed. The optimized catalyst achieves a remarkable urea Faradic efficiency (FE) of 25.2%, significantly outperforming pristine Cu, which predominantly generates ammonia (NH ₃ ). In situ Raman spectroscopy reveals that hydroxyl groups in tannic acid stabilize Cu ^δ+ species, forming a Cu ^δ+ /Cu ⁰ interface under reaction conditions. This interface serves as an active site, facilitating C─N coupling between *CO and *NO intermediates. Density functional theory (DFT) calculations further demonstrate that the Cu ^δ+ /Cu ⁰ interface exhibits a lower energy barrier for C─N coupling both thermodynamically and kinetically‐compared to pristine Cu. This work mitigates uncontrolled catalyst reconstruction during reduction by modulating the electronic structure of Cu through molecular engineering, paving the way for highly selective electrocatalytic urea synthesis.