The effective design and facile preparation of noble metal-free catalysts is crucial for enhancing the performance of rechargeable Li–O₂ batteries. Herein, we report a one-step controlled pyrolysis method to synthesize a Fe/Fe₃C@graphitic carbon shell embedded in carbon nanotubes composite (F@NG-NCNTs) with Prussian blue as the single precursor. In these nanostructures, the Fe/Fe₃C centres induce the formation of self-assembled N-doped carbon frameworks, which in turn offer superior connectivity as well as a protective coating. This novel architecture not only promotes the transfer of electrons but also uniformly encapsulates the catalytically active Fe/Fe₃C nanoparticles, leading to a remarkably enhanced performance in Li–O₂ batteries. As a result, cells catalyzed by the F@NG-NCNTs deliver a higher initial discharge capacity (6966 mA h g⁻¹ at a current density of 0.1 mA cm⁻²) and demonstrate outstanding rate capability and cycle stability. This study verifies that F@NG-NCNTs can be a promising cathode material and provides a new avenue for the effective nanostructural design of electrocatalysts.

中文翻译：

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嵌入普鲁士蓝的碳纳米管中的 Fe / Fe ₃ C @石墨碳壳作为Li–O ₂电池的阴极†

有效设计和简便地制备不含贵金属的催化剂对于增强可充电Li–O ₂电池的性能至关重要。在本文中，我们报告了一种一步控制的热解方法，以普鲁士蓝为单一前驱体合成嵌入在碳纳米管复合材料（F @ NG-NCNTs）中的Fe / Fe ₃ C @石墨碳壳。在这些纳米结构中，Fe / Fe ₃ C中心诱导了自组装的N掺杂碳骨架的形成，这反过来又提供了出色的连接性以及保护性涂层。这种新颖的结构不仅促进了电子的转移，而且均匀地包裹了具有催化活性的Fe / Fe ₃ C纳米颗粒，从而显着提高了Li–O的性能。_2个电池。结果，由F @ NG-NCNT催化的电池提供更高的初始放电容量（在0.1mA cm ^-2的电流密度下为6966mA hg ^-1），并显示出优异的速率能力和循环稳定性。这项研究验证了F @ NG-NCNTs可以成为有前途的阴极材料，并为有效的电催化剂纳米结构设计提供了新途径。