Nitrogen-doped TiO₂–C composite nanofibers (TiO₂/N–C NFs) were manufactured by a convenient and green electrospinning technique in which urea acted as both the nitrogen source and a pore-forming agent. The TiO₂/N–C NFs exhibit a large specific surface area (213.04 m² g⁻¹) and a suitable nitrogen content (5.37 wt%). The large specific surface area can increase the contribution of the extrinsic pseudocapacitance, which greatly enhances the rate capability. Further, the diffusion coefficient of sodium ions (D_Na+) could be greatly improved by the incorporation of nitrogen atoms. Thus, the TiO₂/N–C NFs display excellent electrochemical properties in Na-ion batteries. A TiO₂/N–C NF anode delivers a high reversible discharge capacity of 265.8 mAh g⁻¹ at 0.05 A g⁻¹ and an outstanding long cycling performance even at a high current density (118.1 mAh g⁻¹) with almost no capacity decay at 5 A g⁻¹ over 2000 cycles. Therefore, this work sheds light on the application of TiO₂-based materials in sodium-ion batteries.

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氮掺杂的TiO ₂ -C复合纳米纤维（TiO ₂ / N-C NFs）是通过一种便捷的绿色静电纺丝技术制造的，其中尿素既是氮源又是造孔剂。TiO ₂ / N–C NFs具有较大的比表面积（213.04 m ²  g ^-1）和合适的氮含量（5.37 wt％）。大的比表面积可以增加非本征假电容的贡献，这大大提高了倍率能力。另外，通过引入氮原子，可以大大提高钠离子（D _{Na +}）的扩散系数。因此，TiO ₂/ NC NFs在Na离子电池中显示出优异的电化学性能。TiO ₂ / N–C NF阳极在0.05 A g ^-1时可提供265.8 mAh g ^-1的高可逆放电容量，即使在几乎没有容量的高电流密度（118.1 mAh g ^-1）时也具有出色的长循环性能在2000 A周期内以5 A g ^-1衰减。因此，这项工作揭示了TiO ₂基材料在钠离子电池中的应用。

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