Bi‐Based Metal‐Organic Framework Derived Leafy Bismuth Nanosheets for Carbon Dioxide Electroreduction

Abstract Electroreduction of carbon dioxide (CO 2 ) into high‐value and readily collectable liquid products is vital but remains a substantial challenge due to the lack of highly efficient and robust electrocatalysts. Herein, Bi‐based metal‐organic framework (CAU‐17) derived leafy bismuth nanosheets with a hybrid Bi/BiO interface (Bi NSs) is developed, which enables CO 2 reduction to formic acid (HCOOH) with high activity, selectivity, and stability. Specially, the flow cell configuration is employed to eliminate the diffusion effect of CO 2 molecules and simultaneously achieve considerable current density (200 mA cm −2 ) for industrial application. The faradaic efficiency for transforming CO 2 to HCOOH can achieve over 85 or 90% in 1 m KHCO 3 or KOH for at least 10 h despite a current density that exceeds 200 mA cm −2 , outperforming most of the reported CO 2 electroreduction catalysts. The hybrid Bi/BiO surface of leafy bismuth nanosheets boosts the adsorption of CO 2 and protects the surface structure of the as‐prepared leafy bismuth nanosheets, which benefits its activity and stability for CO 2 electroreduction. This work shows that modifying electrocatalysts by surface oxygen groups is a promising pathway to regulate the activity and stability for selective CO 2 reduction to HCOOH.