Optimizing the Electrocatalytic Selectivity of Carbon Dioxide Reduction Reaction by Regulating the Electronic Structure of Single‐Atom M‐N‐C Materials

Abstract

Electrochemical carbon dioxide reduction reaction (CO 2 RR) is an efficient strategy to relieve global environmental and energy issues by converting excess CO 2 from the atmosphere to value‐added products. Atomically dispersed metal‐nitrogen‐doped carbon (M‐N‐C) materials are superior catalysts for electrocatalytic CO 2 RR because of the 100% atomic utilization, unsaturated coordination configuration, relatively uniform active sites, and well‐defined and adjustable structure of active centers. However, the electrochemical CO 2 RR is a great challenge due to the process involving proton‐coupled multi‐electron transfer with a high energy barrier, which leads to unsatisfactory selectivity to the targeted product, especially for C2 products (e.g., C 2 H 4 and C 2 H 5 OH). Here, the authors systematically summarize effective means, including reasonable selection of isolated metal sites, regulation of the coordination environment of isolated metal atoms, and fabrication of dimetallic single‐atom sites for attaining optimal geometric and electronic structures of M‐N‐C materials and further correlate these structures with catalytic selectivity to various C1 (e.g., CO and CH 4) and C2 products in the CO 2 RR. Moreover, constructive strategies to further optimize M‐N‐C materials for electrocatalytic CO 2 RR are provided. Finally, the challenges and future research directions of the application of M‐N‐C materials for electrocatalytic CO 2 RR are proposed.