The optimized Fe–N–NDC-1-900 exhibits robust anchoring ability to immobilize atomic Fe species with abundant Fe–N4 sites, demonstrating excellent electrocatalytic activity in both the ORR and OER.

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Aluminum–air batteries (AABs) are deemed as a potential clean energy storage device. However, exploiting high‐efficiency and stable oxygen reduction reaction (ORR) electrocatalysts in AABs is still a challenge. Iron phthalocyanine (FePc) shows a great prospect in ORR but still far from Pt‐based catalysts. Here, the hybrid electrocatalysts of monolayer FePc and hollow N,S‐doped carbon spheres (HNSCs) are innovatively constructed through π–π stacking to achieve high dispersion. The resulting FePc@HNSC catalyst exhibits an outstanding ORR activity, outperforming that of pristine FePc and even most Fe‐based catalysts reported to date. Moreover, the AAB using FePc@HNSC catalyst not only demonstrates a superior power density than the battery with Pt/C, but also displays stable discharge voltages and excellent durability. Furthermore, the theoretical calculations confirm that the charge distribution and d‐band center of the Fe atom in FePc are efficiently optimized by hybrid configuration via the introduction of N,S‐doped carbon substrate. The design leads to an enriched electron density around Fe active sites and significant reduction of energy barrier for OH* formation, which are favorable for the improvement of electrocatalytic ORR performance. This work provides a chance to expand the application of metallic macrocyclic compound electrocatalysts in various energy technologies.

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