Zinc-air batteries have recently attracted considerable interest owing to the larger storage capacity and lower cost compared to their lithium-ion counterparts. Electrode catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play a critical role in the operation of rechargeable zinc-air batteries. Herein, we report a simple and scalable strategy to fabricate porous carbon polyhedra using Zn-doped Co-based zeolitic imidazolate frameworks (ZnCo-ZIFs) as precursors. Strikingly, Zn doping leads to smaller Co nanoparticles and higher nitrogen content, which in turn enhances the ORR and OER activities of the obtained porous carbon polyhedra. The synergistic effect of the N-doped carbon and cobalt nanoparticles in the composite, the improved conductivity resulting from the high graphitization of carbon, and the large surface area of the porous polyhedral structure resulted in porous carbon polyhedra with excellent ORR and OER electrocatalytic activity in alkaline media. More importantly, air cathodes based on the optimal porous carbon polyhedra further exhibited superior performance to Pt/C catalysts in primary and rechargeable zinc-air batteries.

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锌空气电池由于与锂离子电池相比具有更大的存储容量和更低的成本，最近引起了人们的极大兴趣。氧还原反应（ORR）和氧释放反应（OER）的电极催化剂在可充电锌空气电池的操作中起着至关重要的作用。在这里，我们报告了一种简单且可扩展的策略，以使用掺杂锌的Co基沸石咪唑酸盐骨架（ZnCo-ZIFs）作为前体来制造多孔碳多面体。令人惊讶的是，Zn掺杂导致更小的Co纳米颗粒和更高的氮含量，这反过来又增强了所得多孔碳多面体的ORR和OER活性。N掺杂的碳和钴纳米颗粒在复合材料中的协同效应，由于碳的高度石墨化而提高了电导率，多孔多面体结构的大表面积导致多孔碳多面体在碱性介质中具有优异的ORR和OER电催化活性。更重要的是，基于最佳多孔碳多面体的空气阴极在原电池和可充电锌空气电池中的表现还优于Pt / C催化剂。

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