Atomically Dispersed Fe Anchored on Nitrogen‐Doped Graphene as Advanced Bifunctional Electrocatalyst for Oxygen Electrode in Rechargeable Zn–Air Battery

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Developing nonprecious metal oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts with both high activity and stability remains a critical challenge for advanced metal–air battery. In this work, we develop a ball‐milling assisted pyrolysis strategy to fabricate atomically dispersed Fe anchored on nitrogen‐doped graphene (Fe–N–C/Gra), which precisely constructs Fe‐N x active centers for efficient ORR/OER bifunctional catalysis. The fabricated Fe–N–C/Gra‐600 demonstrates ORR half‐wave potential of 0.862 V and OER overpotential of 1.743 V at 10 mA cm −2 , surpassing commercial Pt/C benchmarks. Remarkably, under high electrolyte concentration conditions, catalyst exhibits reduced OER overpotentials due to increased electrochemical active surface area and optimized electron transfer resistance. Noteworthy, the Zn–air battery equipped with Fe–N–C/Gra‐600 as air electrode catalyst, delivers a remarkable peak power density of 430 mW cm −2 , along with excellent charge–discharge cycling stability at 10 mA cm −2 . The outstanding bifunctional performance originates from synergistic effects of Fe–N–C/Gra‐600, in which atomically dispersed Fe accelerates adsorption and activation of reactants due to formation of Fe–N x species, synergistically with high conductive property of graphene substrate. This study not only demonstrates great potential of graphene‐supported Fe–N–C single‐atom catalysts for metal–air battery applications but also provides a new strategy for preparing high‐performance nonprecious metal electrocatalysts.