Electrolytic Growth of Hybrid Bi/BiOCl Nanosheets for pH‐Universal Electrocatalytic CO ₂ Reduction Reaction

Abstract To address the challenge of achieving high activity for electrocatalytic CO 2 reduction reaction (eCO 2 RR) to produce formic acid/formate in the pH‐universal media, this study designs a self‐supported electrode with evenly dispersed hybrid metallic bismuth (Bi) and bismuth hypochlorite (BiOCl) nanosheets (Bi/BiOCl NSs) by an electrolytic growth process. Under the negative potential, the Bi salts loaded on the gas diffusion layer is in situ‐reduced to the sheet‐like hybrid Bi/BiOCl nanostructures with abundant active heterojunction sites during the eCO 2 RR process, significantly optimizing the adsorption and conversion pathways of CO 2 . The obtained electrode enables efficient conversion of CO 2 to formic acid under strongly acidic media (pH = 1.3), and formate under alkaline (pH = 14)/neutral (pH = 8.6 and 6.2) electrolytes, with all the peak Faradaic efficiencies exceeding 90%. Additionally, the electrode can operate stably at a high current density of 100 mA cm −2 for 8 hours in pH‐universal media, demonstrating its excellent corrosion resistance and structural stability. This study provides new insights for the design of efficient catalysts for eCO 2 RR in comprehensive environments.