Atomically Dispersed Co<sub>2</sub>MnN<sub>8</sub> Triatomic Sites Anchored in N‐Doped Carbon Enabling Efficient Oxygen Reduction Reaction
Xiaoxiao Yan, Da Liu, Peifang Guo, Yufei He, Xinqiang Wang, Zhenglong Li, Hongge Pan, Dalin Sun, Fang Fang, Renbing Wu
Abstract
Abstract Atomically dispersed transition metal–nitrogen/carbon (M–N/C) catalysts have emerged as the most promising substitutes to the precious platinum counterparts toward the oxygen reduction reaction (ORR). However, the reported M–N/C catalysts are usually in the form of common M–N 4 moieties with only a single metal active site, and they suffer from insufficient activity. Herein, an unusual trinuclear active structure is elaborately developed with a nitrogen‐coordinated single Mn atom adjacent to two Co atoms (Co 2 MnN 8 ) anchored in N‐doped carbon as a highly efficient ORR catalyst via adsorption–pyrolysis of a bimetallic zeolitic imidazolate framework precursor. Atomic structural investigations and density functional theory (DFT) calculations reveal that Co 2 MnN 8 would experience a spontaneous OH binding to form Co 2 MnN 8 ‐2OH as the real active site, leading to a single electron‐filled state in the orbital and an optimized binding energy of intermediates. Accordingly, the as‐developed Co 2 MnN 8 /C exhibits an unprecedented ORR activity with a high half‐wave potential of 0.912 V and outstanding stability, not only surpassing the Pt/C catalyst but also representing a new record for the Co‐based catalyst.