Abstract Anode materials have become one of the primary bottlenecks for the development of rechargeable sodium ion batteries. To explore novel carbon-based anodes enabling high performance sodium storage is urgently desirable but remains quite challenging. Herein, we demonstrates excellent sodium storage performance in nitrogen-doped flexible carbon nanofibers as anodes for sodium ion batteries, through engineering capacitive contribution from regulating surface specific area and porosity. Owing to its unique structural feature and uniform nitrogen doping, the derived free-standing carbon nanofibers film achieves a high reversible capacity of 349.1 mAh g−1 at 50 mA g−1. Even cycled at a high current density of 1 A g−1, the electrode still retains a high capacity of 203.1 mAh g−1 after 1000 extremely stable cycles. The engineering on capacitive contribution in sodium storage might open up possibilities for exploring high performance carbon-based anodes of sodium ion batteries.

中文翻译：

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氮掺杂碳纳米纤维薄膜的工程电容贡献实现高性能钠存储

摘要 负极材料已成为可充电钠离子电池发展的主要瓶颈之一。探索能够实现高性能钠存储的新型碳基阳极是迫切需要的，但仍然非常具有挑战性。在此，我们通过调节表面积和孔隙率的工程电容贡献，证明了作为钠离子电池阳极的氮掺杂柔性碳纳米纤维具有优异的储钠性能。由于其独特的结构特征和均匀的氮掺杂，衍生的自支撑碳纳米纤维薄膜在 50 mA g-1 下实现了 349.1 mAh g-1 的高可逆容量。即使在 1 A g-1 的高电流密度下循环，电极在 1000 次极其稳定的循环后仍保持 203.1 mAh g-1 的高容量。