Low‐Energy CO2 Reduction on a Metal‐Free Carbon Material

Abstract

AbstractElectrochemical CO2 reduction to value‐added chemicals on carbon‐based catalysts is a potential approach for low‐cost value‐added CO2 recycling. However, high overpotential and limited understanding of the mechanism remain challenging. Herein, a nitrogen and phosphorus co‐doped carbon (NPC) material, which is synthesized through a simple pyrolysis, promoted low‐energy electrochemical CO2 reduction. The NPC electrocatalyst combines the advantages of active sites co‐optimized by N and P, faster electrokinetics with bicarbonate providing proton, and more accessible active sites exposed by soft‐template precursors. The NPC electrocatalyst exhibited more than ten‐ and fourfold enhancement of the partial current density of CO production compared to N‐doped and P‐doped carbon materials, respectively, with high selectivity (86 % faradaic efficiency) at only −0.45 V. Experimental data coupled with density function theory calculations revealed that N and P dopants cooperated to enhance CO2 adsorption, first electron transfer to CO2 and then *COOH intermediate stabilization, leading to active and selective CO2‐to‐CO conversion. This work extends the design and understanding of metal‐free carbon‐based electrocatalysts for electrochemical CO2 reduction.