Lattice-dislocated Bi nanosheets for electrocatalytic reduction of carbon dioxide to formate over a wide potential window

Electrochemical reduction of CO₂ to HCOOH (ERC-HCOOH) is one of the most feasible and economically valuable ways to achieve carbon neutrality. Unfortunately, achieving optimal activity and selectivity for ERC-HCOOH remains a challenge. Herein, ultrathin Bi nanosheets (NS) with lattice dislocations (LD-Bi) were prepared by the topological transformation of Bi₂O₂CO₃ NS under high current conditions. LD-Bi exhibited excellent activity and selectivity as well as stability in ERC-HCOOH. Electrochemical tests and DFT calculations revealed that the excellent performance of LD-Bi was attributed to lattice dislocations, which can induce the production of more active sites on the catalyst surface and improve the electronic transfer ability. In addition, LD-Bi was beneficial to enhance the adsorption of CO₂ and key reaction intermediates (OCHO*), thus improving the reaction kinetics. The result provides a unique perspective on the crucial role of lattice dislocations, which may have a significant impact on highly selective electrochemical conversion of CO₂.