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Abstract Urea electrosynthesis from CO 2 and nitrate (NO 3 − ) provides an attractive pathway for storing renewable electricity and substituting traditional energy‐intensive urea synthesis technology. However, the kinetics mismatching between CO 2 reduction and NO 3 − reduction, as well as the difficulty of C─N coupling, are major challenges in urea electrosynthesis. Herein, we first calculated the free energy of *CO, *OCNO, and *NOH formation over defect‐rich Fe 2 O 3 catalysts with different metal dopants, which showed that Zn dopant was a promising candidate. Based on the theoretical study, we developed Zn‐doped defect‐rich Fe 2 O 3 catalysts (Zn–Fe 2 O 3 /O V ) containing asymmetric Zn–O V –Fe sites. It exhibited an outstanding urea faradaic efficiency of 62.4% and the remarkable recycling stability. The production rate of urea was as high as 7.48 mg h −1 mg cat −1 , which is higher than most of the reported works to date. Detailed control experiments and in situ spectroscopy analyses identified *OCNO as a crucial intermediate for C─N coupling. The Zn–Fe 2 O 3 /O V catalyst with asymmetric Zn–O V –Fe sites showed enhanced *CO coverage and promoted *OCNO formation, leading to high efficiency toward urea production.
Song et al. (Tue,) studied this question.