Abstract Fe-N compounds with excellent electrocatalytic oxygen reduction activity are considered to be one of the most promising non-precious metal materials for fuel cells. Fe-N compounds with excellent electrocatalytic oxygen reduction activity are considered to be one of the most promising non-precious metal materials for fuel cells, which focuses on the Fe-N4 single-atom catalysts and the iron nitride materials (such as Fe2N and Fe3N). A hybridized catalyst having a hierarchical porous structure with regular macropores could enable the desired mass transfer efficiency in the catalytic process. In this study, we have constructed a new type of hybrid catalyst having iron and iron-nitrogen alloy nanoparticles (Fe-N austenite, termed as Fe-NA) embedded in the three-dimensional ordered macroporous N-doped carbon (3DOM Fe/Fe-NA@NC) by direct pyrolysis of single-source dicyandiamide-based iron metal-organic frameworks. The as-synthesized composites preserve the hierarchical porous carbon framework with ordered macropores and high specific surface area, incorporating the uniformly dispersed iron/iron-nitrogen austenite nanoparticles. Thereby, the striking architectural configuration embedded with highly active catalytic species delivers a superior oxygen reduction activity with a half-wave potential of 0.88 V and a subsequent superior Zn-air battery performance with high open-circuit voltage and continuous stability as compared to those using a commercial 20% Pt/C catalyst.

中文翻译：

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源自单源金属有机骨架的 3D 有序大孔 N 掺杂碳包封 Fe-N 合金，用于优异的氧还原反应

摘要 Fe-N 化合物具有优异的电催化氧还原活性，被认为是最有前途的燃料电池非贵金属材料之一。具有优异电催化氧还原活性的 Fe-N 化合物被认为是最有前途的燃料电池非贵金属材料之一，主要集中在 Fe-N4 单原子催化剂和氮化铁材料（如 Fe2N 和 Fe3N ）。具有规则大孔的分级多孔结构的杂化催化剂可以在催化过程中实现所需的传质效率。在这项研究中，我们构建了一种具有铁和铁氮合金纳米颗粒（Fe-N 奥氏体、通过单源双氰胺基铁金属有机骨架的直接热解，嵌入三维有序大孔掺氮碳（3DOM Fe/Fe-NA@NC）中。合成的复合材料保留了具有有序大孔和高比表面积的分级多孔碳框架，并结合了均匀分散的铁/铁-氮奥氏体纳米颗粒。因此，嵌入高活性催化物种的引人注目的架构配置提供了卓越的氧还原活性，半波电位为 0.88 V，与使用的锌空气电池相比，具有高开路电压和连续稳定性的锌空气电池性能优异。商用 20% Pt/C 催化剂。合成的复合材料保留了具有有序大孔和高比表面积的分级多孔碳框架，并结合了均匀分散的铁/铁-氮奥氏体纳米颗粒。因此，嵌入高活性催化物种的引人注目的架构配置提供了卓越的氧还原活性，半波电位为 0.88 V，与使用的锌空气电池相比，具有高开路电压和连续稳定性的锌空气电池性能优异。商用 20% Pt/C 催化剂。合成的复合材料保留了具有有序大孔和高比表面积的分级多孔碳框架，并结合了均匀分散的铁/铁-氮奥氏体纳米颗粒。因此，嵌入高活性催化物种的引人注目的架构配置提供了卓越的氧还原活性，半波电位为 0.88 V，随后具有更高的开路电压和连续稳定性的锌空气电池性能，与那些使用商用 20% Pt/C 催化剂。