Defect‐Induced Triple Synergistic Modulation of CuBi Clusters for Enhanced Urea Electrosynthesis

Abstract Electrochemical C–N coupling of CO 2 and NO 3 − is a promising green approach for synthesizing urea. However, achieving efficient C–N coupling remains challenging because of the kinetic mismatch between CO 2 and NO 3 − reduction. Stabilizing key N‐containing intermediates to facilitate their coupling with C‐containing intermediates is crucial for achieving high Faradaic efficiency. In this study, defect‐rich CuBi clusters (D‐CuBi) were synthesized, and the effects of the enhanced functionalities of the defects of D‐CuBi on the performance of urea synthesis at different critical processes were systematically investigated. Density functional theory calculations and in situ electrochemical spectroscopic analysis revealed that the defects in D‐CuBi facilitated the adsorption of CO 2 and prevented the desorption of the key *NO 2 intermediate as NO 2 − . Moreover, these sites facilitated the adsorption of active water molecules, thereby accelerating the reaction kinetics for urea production. As a result, the D‐CuBi catalyst achieved a remarkable urea Faradaic efficiency of 53.1% and a yield rate of 2.57 µmol h −1 cm −2 at −1.0 V vs. the reversible hydrogen electrode, representing an approximately tenfold enhancement over the intact CuBi. This work presents insight into urea electrosynthesis from CO 2 and NO 3 − through defect engineering.