In‐Induced Electronic Structure Modulations of Bi─O Active Sites for Selective Carbon Dioxide Electroreduction to Liquid Fuel in Strong Acid

Abstract The formation of carbonate in neutral/alkaline solutions leads to carbonate crossover, severely reducing carbon dioxide (CO 2 ) single pass conversion efficiency (SPCE). Thus, CO 2 electrolysis is a prospective route to achieve high CO 2 utilization under acidic environment. Bimetallic Bi‐based catalysts obtained utilizing metal doping strategies exhibit enhanced CO 2 ‐to‐formic acid (HCOOH) selectivity in alkaline/neutral media. However, achieving high HCOOH selectivity remains challenging in acidic media. To this end, Indium (In) doped Bi2O2CO3 via hydrothermal method is prepared for in‐situ electroreduction to In‐Bi/BiOx nanosheets for acidic CO2 reduction reaction (CO2RR). In doping strategy regulates the electronic structure of Bi, promoting the fast derivatization of Bi2O2CO3 into Bi‐O active sites to enhance CO2RR catalytic activity. The optimized Bi 2 O 2 CO 3 ‐derived catalyst achieves the maximum HCOOH faradaic efficiency (FE) of 96% at 200 mA cm −2 . The SPCE for HCOOH production in acid is up to 36.6%, 2.2‐fold higher than the best reported catalysts in alkaline environment. Furthermore, in situ Raman and X‐ray photoelectron spectroscopy demonstrate that In‐induced electronic structure modulation promotes a rapid structural evolution from nanobulks to Bi/BiO x nanosheets with more active species under acidic CO 2 RR, which is a major factor in performance improvement.