Boron‐Doped Nickel–Nitrogen–Carbon Single‐Atom Catalyst for Boosting Electrochemical CO₂ Reduction

Abstract Tuning the coordination environment of the metal center in metal–nitrogen–carbon (M–N–C) single‐atom catalysts via heteroatom‐doping (oxygen, phosphorus, sulfur, etc.) is effective for promoting electrocatalytic CO 2 reduction reaction (CO 2 RR). However, few studies are investigated establishing efficient CO 2 reduction by introducing boron (B) atoms to regulate the M–N–C structure. Herein, a B‐C 3 N 4 self‐sacrifice strategy is developed to synthesize B, N co‐coordinated Ni single atom catalyst (Ni‐BNC). X‐ray absorption spectroscopy and high‐angle annular dark field scanning transmission electron microscopy confirm the structure (Ni‐N 3 B/C). The Ni‐BNC catalyst presents a maximum CO Faradaic efficiency (FE CO ) of 98.8% and a large CO current density ( j CO ) of −62.9 mA cm −2 at −0.75 and −1.05 V versus reversible hydrogen electrode, respectively. Furthermore, FE CO could be maintained above 95% in a wide range of potential windows from −0.65 to −1.05 V. In situ experiments and density functional theory calculations demonstrate the Ni‐BNC catalyst with B atoms coordinated to the central Ni atoms could significantly reduce the energy barrier for the conversion of *CO 2 to *COOH, leading to excellent CO 2 RR performance.