A Nanocomposite of Bismuth Clusters and Bi₂O₂CO₃ Sheets for Highly Efficient Electrocatalytic Reduction of CO₂ to Formate

Abstract

The renewable-electricity-driven CO₂ reduction to formic acid would contribute to establishing a carbon-neutral society. The current catalyst suffers from limited activity and stability under high selectivity and the ambiguous nature of active sites. Herein, we report a powerful Bi₂ S₃ -derived catalyst that demonstrates a current density of 2.0 A cm^-2 with a formate Faradaic efficiency of 93 % at -0.95 V versus the reversible hydrogen electrode. The energy conversion efficiency and single-pass yield of formate reach 80 % and 67 %, respectively, and the durability reaches 100 h at an industrial-relevant current density. Pure formic acid with a concentration of 3.5 mol L^-1 has been produced continuously. Our operando spectroscopic and theoretical studies reveal the dynamic evolution of the catalyst into a nanocomposite composed of Bi⁰ clusters and Bi₂ O₂ CO₃ nanosheets and the pivotal role of Bi⁰ -Bi₂ O₂ CO₃ interface in CO₂ activation and conversion.