Although rechargeable lithium-sulfur batteries (LSBs) are next generation energy storage devices, severe shuttle effect and sluggish multi-electron redox reactions compromise the practical application of LSBs. To address these issues and enable the manufacture of robust LSBs, here the use of Fe₃C-Fe₃P heterostructure encapsulated in nitrogen–doped carbon nanotubes (FeCP@NCNT) was synthesized. The tubular geometry of FeCP@NCNT provided buffering void to suppress volume change, and afforded conductive network to expedite the diffusion of Li⁺, as well as endowed plenteous active sites to absorb and catalyze the transformation of LiPSs during charge-discharge cycles. Experimental data proved that FeCP@NCNT could strengthen the “anchoring of lithium polysulfides (LiPSs)” (by Fe₃P) and expedite the “diffusion of intermediate” (by CNT) as well as accelerate the “catalytic phase conversion” (by Fe₃C), resulting in balanced “trapping-diffusion-conversion” dynamic process. Notably, FeCP-3h@NCNT/G/S attained an initial capacity of 1127 mAh g⁻¹ with a low decay rate of 0.12% at 1 C for 300 cycles Moreover, FeCP-3h@NCNT/G/S delivered excellent battery performances under high currents of 2 and 5 C for 500 cycles. This work felicitously proposed the strategy to fabricate metal carbide-phosphide heterostructure electrocatalyst for high-performance LSBs.

尽管可充电锂硫电池 (LSB) 是下一代储能设备，但严重的穿梭效应和缓慢的多电子氧化还原反应阻碍了 LSB 的实际应用。为了解决这些问题并能够制造坚固的 LSB，这里合成了封装在氮掺杂碳纳米管中的Fe ₃ C-Fe _{3 P 异质结构 (FeCP@NCNT)。}^{FeCP@NCNT 的管状几何形状提供缓冲空隙以抑制体积变化，并提供导电网络以加速 Li +}的扩散，以及赋予丰富的活性位点以在充放电循环期间吸收和催化 LiPSs 的转化。实验数据证明，FeCP@NCNT可以加强“多硫化锂(LiPSs)的锚定”(by Fe ₃ P)，加速“中间体扩散”(by CNT)，加速“催化相转化”(by Fe) ₃ C)，导致平衡的“捕获-扩散-转化”动态过程。值得注意的是，FeCP-3h@NCNT/G/S 的初始容量达到了 1127 mAh g ⁻¹FeCP-3h@NCNT/G/S 在 1 C 下循环 300 次，衰减率为 0.12% 的低衰减率此外，FeCP-3h@NCNT/G/S 在 2 C 和 5 C 的大电流下循环 500 次，具有出色的电池性能。这项工作成功地提出了制造用于高性能 LSB 的金属碳化物-磷化物异质结构电催化剂的策略。