Selective Electrochemical CO2 Reduction tuned by N Configuration on graphitic Shells of Nickel Particles

Abstract Despite of high conductivity and reducing ability, transition metal nanoparticles tend to aggregate and unavoidably impact the selectivity during the proton‐coupled reduction process of CO 2 RR. New strategy to regulate and utilize the electronic property of transition‐metal particles allows for effective tuning of eCO 2 RR activity. Through simple creation of N‐doped carbon shells surrounding Ni nanoparticles and controlling the amount and arrangement of the N atoms, successful and long‐lasting electrochemical reduction of CO 2 was accomplished. The inherent HER activity was almost completely suppressed. It exhibited FE CO above 90 % in a 500 mV potential window, with the optimal up to 96.5 % at −0.78 V vs RHE. In flow cell electrolysis, a current density of 289.4 mA/cm 2 was achieved with Faradic efficiency of 96.4 % towards CO. The results of control experiments using different catalysts imply that electron transfer between Ni core and shells was significantly influenced by the property of N atoms. High content of graphitic nitrogen is crucial for the catalytic performance.