Iron sulfides draw much attention as electrode candidates for sodium-ion batteries (SIBs) due to the rich chemical stoichiometries and high capacity. However, they usually exhibit poor cycling performance due to the large volume change during sodiation/desodiation process. In this work, we embed Fe₇S₈ nanoparticles into sulfur, nitrogen-doped carbon (S/N–C) nanofibers through electrospinning/sulfurization processes. The heteroatom doped carbon matrixes could effectively protect the Fe₇S₈ from structural collapse, obtaining a stable cycling performance. Moreover, the conductive matrixes with 1D structure can facilitate the diffusion of electrons, leading to good rate capability. As results, the as-designed Fe₇S₈@S/N–C nanofibers present a discharge capacity of 347 m Ah g⁻¹ after 150 cycles at 1 A g⁻¹ and a high rate capacity of 220 m Ah g⁻¹ at 5 A g⁻¹ in virtue of unique structural characteristics.

硫化铁作为钠离子电池（SIB）的候选电极，由于其丰富的化学计量比和高容量而备受关注。但是，由于在加糖/脱糖过程中体积变化较大，它们通常表现出较差的循环性能。在这项工作中，我们通过电纺/硫化工艺将Fe ₇ S ₈纳米颗粒嵌入硫，氮掺杂的碳（S / N–C）纳米纤维中。杂原子掺杂的碳基体可以有效地保护Fe ₇ S ₈免受结构破坏，获得稳定的循环性能。此外，具有一维结构的导电基体可以促进电子的扩散，从而导致良好的速率能力。结果，设计好的Fe ₇S ₈ @ S / N–C纳米纤维在1 A g ^-1下经过150次循环后的放电容量为347 m Ah g ^-1，在5 A g ^-1下具有220 m Ah g ^-1的高倍率容量。独特的结构特征。