Twin‐Boundary Cu 2 ‐Pair Pockets Drive Spatial Proximity of Key Intermediates for Efficient Urea Electrosynthesis

ABSTRACT Electrocatalytic urea synthesis from carbon dioxide (CO 2 ) and nitrate (NO 3 − ) offers an alternative to the energy‐intensive Bosch‐Meiser process but is limited by poor selectivity and Faradaic efficiency (FE). Herein, we proposed a defect engineering strategy by constructing ordered Cu nanowire electrocatalysts enriched with abundant twin boundaries (TBs) that can drive spatial proximity between the key intermediates derived from asymmetric activation of CO 2 and optimized adsorption of NO 3 − . Specifically, it could achieve a high FE of 61.81% and a peak yield rate of 5.80 mg h −1 cm −2 for urea production under a three‐electrode configuration. The underlying mechanism can be described as the TB‐induced compression shortening the Cu–Cu bond, creating Cu 2 ‐pair pockets that geometrically matched CO 2 adsorption and enabled asymmetric activation to *CO, further strengthening Cu → CO π back‐donation and building a *CO reservoir. Smoluchowski smoothing rendered ridge Cu sites electron‐deficient, enriching NO 3 − near Cu 2 ‐pair pockets for C–N coupling.