Intrinsic Electrocatalytic Activity Regulation of M–N–C Single‐Atom Catalysts for the Oxygen Reduction Reaction

• Published in: Angewandte Chemie International Edition Vol. 60; no. 9; pp. 4448 - 4463
• Main Authors: Zhao, Chang‐Xin, Li, Bo‐Quan, Liu, Jia‐Ning, Zhang, Qiang
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 23.02.2021
• Edition: International ed. in English
• Subjects: Catalysts; Chemical reactions; Chemical reduction; electrocatalysis; electronic structure; fuel cells; Oxidation; Oxygen; oxygen reduction reaction; Oxygen reduction reactions; Single atom catalysts; singleatom catalysts; Substrates; Transition metals; fuel cells; singleatom catalysts; oxygen reduction reaction; electrocatalysis; electronic structure
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202003917

Single‐atom catalysts (SACs) with highly active sites atomically dispersed on substrates exhibit unique advantages regarding maximum atomic efficiency, abundant chemical structures, and extraordinary catalytic performances for multiple important reactions. In particular, M–N–C SACs (M=transition metal atom) demonstrate optimal electrocatalytic activity for the oxygen reduction reaction (ORR) and have attracted extensive attention recently. Despite substantial efforts in fabricating various M–N–C SACs, the principles for regulating the intrinsic electrocatalytic activity of their active sites have not been sufficiently studied. In this Review, we summarize the regulation strategies for promoting the intrinsic electrocatalytic ORR activity of M–N–C SACs by modulation of the center metal atoms, the coordinated atoms, the environmental atoms, and the guest groups. Theoretical calculations and experimental investigations are both included to afford a comprehensive understanding of the structure–performance relationship. Finally, future directions of developing advanced M–N–C SACs for electrocatalytic ORR and other analogous reactions are proposed. Regulation strategies for enhancing the intrinsic electrocatalytic oxygen reduction reaction activity of M–N–C single‐atom catalysts are summarized in this review. Four components are considered in the optimization of the catalyst: the center metal atoms, the coordinated atoms, the environmental atoms, and the guest groups.