Copper/Carbon Heterogenous Interfaces for Enhanced Selective Electrocatalytic Reduction of CO2 to Formate

Abstract Electrochemical reduction of CO2 (CO2RR) to formate is a promising route to prepare value‐added chemical. Developing low‐cost and efficient electrocatalysts with high product selectivity is still a grand challenge. Herein, a novel Cu anchored on hollow carbon spheres catalysts (HCS/Cu‐x, x represents the mass of CuCl2 added in the system) is designed with controllable copper/carbon heterogenous interfaces. Rich copper/carbon heterogenous interfaces and hollow structure of optimized HCS/Cu‐0.12 catalyst are beneficial to charge transmission. Compared with the CO2RR occurred in aqueous electrolyte over Cu‐based catalyst that has been reported to date, it exhibits highest formate Faradaic efficiency (FE) of 82.4% with a current density of 26 mA cm−2 and remarkable stability in a H‐cell.