Interface-Induced Electrocatalytic Enhancement of CO2-to-Formate Conversion on Heterostructured Bismuth-Based Catalysts

Electrochemical CO₂ reduction reaction (CO₂RR) is a promising approach to convert CO₂ to carbon-neutral fuels using external electric powers. Here, the Bi₂S₃-Bi₂O₃ nanosheets possessing substantial interface being exposed between the connection of Bi₂S₃ and Bi₂O₃ are prepared and subsequently demonstrate to improve CO₂RR performance. The electrocatalyst shows formate Faradaic efficiency (FE) of over 90% in a wide potential window. A high partial current density of about 200 mA cm^?2 at ?1.1 V and an ultralow onset potential with formate FE of 90% are achieved in a flow cell. The excellent electrocatalytic activity is attributed to the fast-interfacial charge transfer induced by the electronic interaction at the interface, the increased number of active sites, and the improved CO₂ adsorption ability. These collectively contribute to the faster reaction kinetics and improved selectivity and consequently, guarantee the superb CO₂RR performance. This study provides an appealing strategy for the rational design of electrocatalysts to enhance catalytic performance by improving the charge transfer ability through constructing a functional heterostructure, which enables interface engineering toward more efficient CO₂RR.