Zeolitic imidazolate frameworks (ZIFs) are a subclass of metal–organic frameworks (MOFs). These robust, porous materials have garnered significant interest because of their outstanding properties as catalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Herein, the synthesis of Co‐ and Ni‐containing ZIF‐67 embedded in carbon nanotubes (CNTs) to be used as a cathode material for rechargeable zinc–air batteries is described. Carbon‐nanotube‐encapsulated metallic Co and Ni form via calcination of the MOF at 700 °C for 4 h and are characterized by X‐ray diffraction and transmission electron microscopy (TEM). Co and Ni graphitization within the CNTs is analyzed by Raman spectroscopy, and morphologies are assessed by scanning electron microscopy (SEM) and TEM. Excellent electrochemical performance of the prepared catalysts during charging and discharging reveals that the catalyst is stable for well over 500 h. Moreover, superior OER performance is observed when CNT@Co or CNT@Ni is used as a bifunctional catalyst in the zinc–air battery.

中文翻译：

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过渡金属（钴或镍）封装在由碳氮杂咪唑酸酯骨架（ZIFs）制成的碳纳米管中，作为双功能催化剂，用于氧还原和放出反应

沸石咪唑盐骨架（ZIF）是金属有机骨架（MOF）的子类。这些坚固，多孔的材料因其作为氧气析出反应（OER）和氧气还原反应（ORR）的出色性能而备受关注。本文描述了嵌入碳纳米管（CNT）中的钴和镍ZIF-67的合成方法，该碳纳米管用作可充电锌空气电池的阴极材料。碳纳米管包裹的金属Co和Ni通过MOF在700°C下煅烧4 h形成，并通过X射线衍射和透射电子显微镜（TEM）表征。碳纳米管中的Co和Ni石墨化通过拉曼光谱分析，并通过扫描电子显微镜（SEM）和TEM评估形态。制备的催化剂在充电和放电过程中的优异电化学性能表明，该催化剂在超过500小时内稳定。此外，当在锌-空气电池中使用CNT @ Co或CNT @ Ni作为双功能催化剂时，可以观察到卓越的OER性能。