Chemical Engineering Journal ( IF 13.3 ) Pub Date : 2023-02-08 , DOI: 10.1016/j.cej.2023.141794
Kaixiang Shi , Yajie Sun , Zhangshi Xiong , Junhao Li , Haoxiong Nan , Yongxian Lin , Zhigang Wei , Quanbing Liu
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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.
中文翻译:

在高性能锂硫电池的异质结构 Fe3C-Fe3P 促进剂中实现多硫化物吸附和催化转化之间的平衡行为
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。