The rational design and preparation of nonprecious metal-based oxygen reduction reaction (ORR) catalysts to facilitate electron and mass transport are of great significance in oxygen-involved energy applications. Herein, a stepwise approach to synthesize a type of hierarchically porous N-doped carbon nanotubes (CNTs) grafted onto zinc-based coordination polymer derived carbon nanomaterials (M-NCNT, M = Fe/Co/Ni) is proposed. At first, an isostructural zinc-based metal-organic framework (MOF) to HKUST-1(Cu) (ZnHKUST-1) is solvothermally prepared, and then under pyrolysis to obtain MOF-derived porous carbon. After the secondary calcination, the in-situ formed N-doped CNTs are efficiently catalyzed by iron group metal-based nanoparticles (Fe/Co/Ni), which are thermally reduced by porous carbon together with additional urea. The synergistic effect between ultrahigh porosity, large surface area, suitable N-doping, high graphitization degree, and ultrafine metal particles prompts M-NCNT series to exhibit satisfactory electrocatalysis in oxygen reduction. Among them, Fe-NCNT owns the optimal ORR activity with high positive onset potential (0.987 V), half-wave potential (0.860 V) and large diffusion-limited current density (4.893 mA cm^-2). Meanwhile, it shows a high current retention of 91.9% after the 10-hour stability, and the obtained Zn-air battery by Fe-NCNT with open-circuit voltage of 1.44 V owns moderate capacity and satisfying stability. The demonstrated method to prepare hierarchically porous N-doped carbon nanomaterials stemmed from MOF precursors unfolds a new route for the facile construction of efficient nanocatalysts for advanced energy applications.

合理设计和制备基于非贵金属的氧还原反应（ORR）催化剂以促进电子和质量传输，在涉及氧的能源应用中具有重要意义。在此，提出了一种逐步合成一种接枝到锌基配位聚合物衍生的碳纳米材料（M-NCNT，M = Fe/Co/Ni）上的分级多孔 N 掺杂碳纳米管（CNT）的方法。首先，溶剂热制备了等结构的锌基金属有机骨架（MOF）与HKUST-1（Cu）（ZnHKUST-1），然后在热解下获得MOF衍生的多孔碳。二次煅烧后，原位形成的 N 掺杂 CNT 由铁族金属基纳米粒子 (Fe/Co/Ni) 有效催化，这些纳米粒子被多孔碳和额外的尿素热还原。超高孔隙率、大表面积、适当的N掺杂、高石墨化度和超细金属颗粒之间的协同作用促使M-NCNT系列在氧还原中表现出令人满意的电催化作用。其中，Fe-NCNT具有最佳的ORR活性，具有高正起始电位（0.987 V）、半波电位（0.860 V）和大扩散限制电流密度（4.893 mA cm ^-2）。同时，它在 10 小时的稳定性后显示出 91.9% 的高电流保持率，并且通过Fe-NCNT获得的锌空气电池开路电压1.44V，容量适中，稳定性令人满意。制备源自 MOF 前体的分层多孔 N 掺杂碳纳米材料的证明方法为轻松构建用于先进能源应用的高效纳米催化剂开辟了一条新途径。