Enhancement of Mass Transfer for Facilitating Industrial‐Level CO2 Electroreduction on Atomic NiN4 Sites

Abstract Herein, an active catalyst A‐Ni@CMK is developed with the atomically dispersed NiN 4 moieties on the mesoporous carbon for the electrocatalytic CO 2 reduction reaction (CO 2 RR) through a step‐by‐step pore‐filling synthetic strategy. Concretely, the as‐synthesized catalyst A‐Ni@CMK exhibits outstanding catalytic performance for CO 2 RR in the H‐cell with a Faradaic efficiency of CO (FE CO ) > 80% in a wide electrochemical potential window (−0.5 to −0.9 V vs RHE) and a large CO partial current density ( j CO ) of 24 and 51 mA cm −2 at −0.6 and −0.8 V versus RHE, respectively. Notably, j CO for A‐Ni@CMK can further reach the industrial‐level values of 366 mA cm −2 at −0.8 V versus RHE, respectively, with the FE CO > 95% in the flow cell, surpassing those for all the thus far reported NiNC catalysts and representing one of the best values for the catalysts for CO 2 RR. Moreover, comparative experimental studies in combination with density functional theory calculations demonstrate that the intrinsic high activity of the atomic NiN 4 sites towards CO 2 RR results in high selectivity. Nevertheless, the mesoporous channels favor the mass transmission for both reactant CO 2 and gas‐product CO, which in turn enhances the reaction kinetics, leading to the improved overall performance of the as‐prepared A‐Ni@CMK catalyst for CO 2 ‐to‐CO conversion.