Herein, a N, S co-doped carbon encapsulating Co 9 S 8 nanoparticles (Co 9 S 8 @N, S-C) catalyst is successfully synthesized by a new precursor of Co-pyridine coordinated-polymer consisting of 2,6-diacetylpyridine and 4,4′-dithiodianiline. Benefiting from the abundant pore-structure (average pore-size ≈25nm) and unique electronic-properties of the Co 9 S 8 and N, S-C layer, the as-prepared Co 9 S 8 @N, S-C exhibits rapid oxygen reduction reaction (ORR) kinetics with high electron transfer number of ≈3.998 and demonstrates a low overpotential of 304 mV for the oxygen evolution reaction (OER). It exhibits a small potential difference of 0.647V for overall ORR/OER activity, outperforming most of the non-precious metal-catalysts previously reported. The rechargeable Zn-Air battery test further demonstrates its excellent activity and stability, in which the battery delivers a maximum power density output of 259 mW cm −2 , a specific capacity of 862 mAh g Zn −1 , and after continuous 110 h operation the charge-discharge round-trip efficiency only reduces by 4.83%. Theoretical calculation studies show that the surface N, S-C layers and Co 9 S 8 can adjust each other's Fermi levels, so that the adsorption energy of Co 9 S 8 @N, S-C on O intermediate is more favorable than using Co 9 S 8 and N, S-C alone. This study reveals the structure-function relationship of coated-nanostructures with multifunctional electrocatalytic properties, and provides a feasible strategy for the design of non-noble metal-catalysts.

Nonprecious group metal (NPGM)‐based single atom catalysts (SACs) hold a great potential in electrocatalysis and dopant engineering has been extensively exploited to boost their catalytic activity, while the coordination environment of dopant, which also significantly affects the electronic structure of SACs, and consequently their electrocatalytic performance, have been largely ignored. Here, by adopting a precursor modulation strategy, the authors successfully synthesize single cobalt atom catalysts embedded in nitrogen‐doped carbon, Co–N/C, with similar overall Co and N concentrations but different N types, that is, pyridinic N (NP), graphitic N (NG), and pyrrolic N (NPY). Co–N/C with the Co–N4 moieties coordinated with NG displays far superior activity for oxygen reduction (ORR) and evolution reactions, and superior activity and stability in both zinc–air batteries and proton exchange membrane fuel cells. Density functional theory calculation indicates that coordinated N species in particular NG functions as electron donors to the Co core of Co–N4 active sites, leading to the downshift of d‐band center of Co–N4 and weakening the binding energies of the intermediates on Co–N4 sites, thus, significantly promoting catalytic kinetics and thermodynamics for ORR in a full pH range condition.

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