N-bridged Ni and Mn single-atom pair sites: A highly efficient electrocatalyst for CO2 conversion to CO

Abstract

Herein, we report highly efficient diatomic electrocatalysts with Ni and Mn single-atom pair sites decorated on N-doped porous carbon framework for CO2 conversion. The resulting catalysts can preferentially and rapidly convert CO2 into CO with a high Faradaic efficiency of 98.3% and an industrially relevant current density of – 300 mA cm−2 at a low overpotential of 0.287 V in a GDE-based flow reactor cell. Furthermore, it shows high cathodic energetic efficiencies over 80 % for CO production even under industrially relevant current densities. The in-depth experimental measurements and theoretical calculations reveal that the synergistic electronic modification effect caused by coupling neighboring Ni and Mn single atoms exhibits favorable characteristics in reaction steps of CO2 conversion such as CO2 adsorption/activation and immobilization of CO2 radical intermediate as well as adsorbed CO desorption, leading to highly efficient CO production.