Boosting CO₂ Electroreduction on Bismuth Nanoplates with a Three-Dimensional Nitrogen-Doped Graphene Aerogel Matrix

Electrochemical CO 2 reduction reaction (CO 2 RR), which uses renewable electricity to produce high-value-added chemicals, offers an alternative clean path to the carbon cycle. However, bismuth-based catalysts show great potential for the conversion of CO 2 and water to formate, but their overall efficiency is still hampered by the weak CO 2 adsorption, low electrical conductivity, and slow mass transfer of CO 2 molecules. Herein, we report that a rationally modulated nitrogen-doped graphene aerogel matrix (NGA) can significantly enhance the CO 2 RR performance of bismuth nanoplates (BiNPs) by both modulating the electronic structure of bismuth and regulating the interface for chemical reaction and mass transfer environments. In particular, the NGA prepared by reducing graphene oxide (GO) with hydrazine hydrate (denoted as NGA hdrz ) exhibits significantly enhanced strong metal–support interaction (SMSI), increased specific surface area, strengthened CO 2 adsorption, and modulated wettability. As a result, the Bi/NGA hdrz exhibits significantly boosted CO 2 RR properties, with a Faradaic efficiency (FE) of 96.4% at a current density of 51.4 mA cm –2 for formate evolution at a potential of −1.0 V versus reversible hydrogen electrode (vs RHE) in aqueous solution under ambient conditions.