Synthesis of Few-Layer Bismuthene for Efficient Electroreduction of CO₂ to Formate

Bismuth (Bi) nanosheets are considered an auspicious electrocatalyst for CO2 reduction. Herein, we report a facile bottom-up synthesis toward few-layer bismuthene (f-bismuthene) with a hydrophobic surface, which shows high activity over a wide potential window of 400 mV and maintains over 80.4% formate Faradaic efficiencies (FEformate) after 45 h in an H-type electrolytic cell. Remarkably, the f-bismuthene achieves a maximum formate partial current density of 419.4 mA cm(-2) and FEformate of 96.9% in the flow cell. This work shall provide a valuable strategy toward the development of highly efficient electrocatalysts for CO2 reduction.