WSe 2 Crystal Facet Engineering Boosting Rapid Conversion and Deposition of Lithium Polysulfides

In response to the global energy crisis and growing environmental awareness, lithium–sulfur batteries (LSBs) have attracted considerable attention as a promising candidate for energy storage systems due to their high theoretical energy density. Nevertheless, the practical application of LSBs is impeded by the polysulfide-induced “shuttle effect” (Li 2 S n, where n = 2–8) and the poor electrical conductivity of elemental sulfur (S 8 ) and lithium sulfide (Li 2 S). To mitigate these challenges, this study introduces a WSe 2 @NCNFs interlayer synthesized by compositing WSe 2 with nitrogen-doped carbon nanofibers (NCNFs) through electrospinning. This composite not only stabilizes the two-dimensional (2D) WSe 2 structure with substantial catalytic activity but also facilitates the growth of WSe 2 on carbon nanosurfaces with abundant exposed (100) crystal planes and grain boundaries. These characteristics significantly enhance lithium polysulfides (LiPSs) adsorption and catalytic conversion while providing extensive nucleation sites for Li 2 S. Experimental results indicate that batteries utilizing the WSe 2 @NCNFs interlayer exhibit superior cycling stability and rate performance. This crystal engineering strategy presents an innovative approach to enhancing the overall performance of LSBs.