Oxygen vacancy stabilized <scp> Bi ₂ O ₂ CO ₃ </scp> nanosheet for <scp> CO ₂ </scp> electroreduction at low overpotential enables energy efficient CO‐production of formate

Bismuth-based electrocatalysts are promising candidates for electrochemical CO2 reduction to formate attributing the accelerated formation of *OCHO intermediate, while high-energy consumption remains a major challenge practicability. Herein, we present ultrathin Bi2O2CO3 nanosheets with abundant oxygen vacancy (Vo-BOC-NS) reconstructed from S, N-co-doped bismuth oxides that can act as durable electrocatalyst CO2-to-formate conversion faradic efficiency (FEformate) >95%, partial current density 286 mA cm−2 energy 73.8% at −0.62 V (vs. RHE) and low overpotential 200 mV in flow electrolyzer. The theoretical calculations decipher optimize *OCOH adsorption/desorption kinetics. pair-electrosynthesis tactic co-production enable superior FEformate >90% wide cell voltage 2–3.3 total yield rate 3742 μmol h−1 3.3 V, suggesting great potential future industrialization.