Na-O₂ batteries have drawn increasing attention in recent years, owing to their high energy density and the abundance of sodium resources. Their applications still suffer, however, from lack of effective air cathodes to achieve a stable and long cycle life. Herein, we report a nitrogen-doped carbon nanofiber (NCF) material derived from polypyrrole as air cathode for the non-aqueous Na-O₂ electrochemical system. Notably, Na-O₂ batteries with NCF as air cathode could achieve a low overpotential gap of 500 mV, a high specific capacity of 8554.7 mA h g⁻¹ at 100 mA g⁻¹, and excellent cyclic stability over 90 cycles with NaO₂ as the discharge product. These excellent performances can be attributed to the combination of their highly conductive three-dimensional network structure, large surface area, and superior catalytic activity, obtained by incorporating nitrogen atoms into the carbon matrix, which can facilitate electron transportation, oxygen and electrolyte diffusion, and discharge product deposition and decomposition. Besides, density functional theory (DFT) calculations indicated that pyrrolic and pyridinic-N doping can effectively optimize the surface adsorption energy of the reactants and intermediate, which facilitate to achieve excellent oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity. The results reported here can point the way to the rational design of electrocatalytic air cathodes for rechargeable Na-O₂ batteries.

近年来，Na-O ₂电池由于其高能量密度和丰富的钠资源而受到越来越多的关注。然而，它们的应用仍然受到缺乏有效的空气阴极以实现稳定和长循环寿命的困扰。在这里，我们报告了一种由聚吡咯衍生的氮掺杂碳纳米纤维（NCF）材料，作为非水Na-O ₂电化学体系的空气阴极。值得注意的是，以NCF作为空气阴极的Na-O ₂电池可以实现500 mV的低过电势差，在100 mA g ^-1时具有8554.7 mA h g ^-1的高比容量，以及在使用NaO _{2的情况下}在90个循环中具有出色的循环稳定性作为放电产物。这些优异的性能归因于其高导电性的三维网络结构，大的表面积和出色的催化活性的组合，这些优点是通过将氮原子掺入碳基体中而获得的，从而可以促进电子传输，氧气和电解质的扩散，以及放电产物沉积和分解。此外，密度泛函理论（DFT）计算表明，吡咯和N掺杂可以有效优化反应物和中间体的表面吸附能，有利于实现优异的氧还原反应（ORR）和氧释放反应（OER）活性。此处报告的结果可为合理设计可充电Na-O电催化空气阴极的方法_2个电池。