In situ reduction growth Sn-MoS2 on CNFs as advanced separator coating for improved-performance lithium sulfur batteries

Separator modification is a promising strategy to solve the issues of terrible "shuttle effect" and sluggish conversion of lithium polysulfides (LiPSs) in Lithium-sulfur batteries (LSBs). Herein, we fabricated an intriguing architecture of tin-molybdenum disulfide (Sn-MoS2) heterostructure uniformly distributed on carbon nanofibers (Sn-MoS2/CNFs) by the incorporation of electrospinning technology and the in-situ reduction methods to modify the separator for LSBs. The Sn reduced from tin oxide (SnO2) in carbon nanofiber can not only facilitate the rapid ion and electron migration but also promote the porous structure obtained by the reduction collapse process. Furthermore, the heterostructure of MoS2 and Sn uniformly and stably dispersed on the carbon nanofiber and effectively served as both chemical adsorption carriers and electrocatalysts to enhance the LiPSs anchoring and the conversion reaction kinetics. In result, the initial discharge specific capacity at 0.2 C can achieve 1332.8 mAh g−1, while the capacity remains at 579.3 mAh·g−1 after 200 cycles for the LSBs with the Sn-MoS2/CNFs separators. We believe that the experimental results offer a feasible method to design high-performance separators for LSBs.