Lithium sulfur batteries have been regarded as promising energy storage devices due to their superiority in energy density. However, the low sulfur loading, low active material utilization, and poor cycling stability restrict their commercial applications. Herein, we prepared a three-dimensional structure of SnS 2 nanoplates decorated on nitrogen-doped carbon nanofibers (3D SnS 2 @N-CNFs) by an electrospinning process followed by a hydrothermal technique. The 3D freestanding SnS 2 @N-CNFs were applied as the current collector and polymeric binder containing a Li 2 S 6 catholyte for lithium polysulfide batteries. The obtained SnS 2 @N-CNFs show the strong physicochemical adsorption of polysulfides and can effectively reduce the electrochemical polarization. The cell with SnS 2 @N-CNFs exhibits high electrochemical performance. As a result, SnS 2 @N-CNFs with high sulfur loading of approximately 7.11 mg displayed the first discharge capacity of 1010 mAh g −1 at 0.2 C with 0.08% capacity decay per cycle over 150 cycles. Meanwhile, the electrode with sulfur loading up to 22.65 mg also exhibits an extremely high capacity of 14.67 mAh, much higher than commonly presented blade-cast sulfur electrodes. The fibrous membrane is promising for assembling with high sulfur loading, which exhibits a superior electrochemical performance in lithium sulfur batteries.

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Lithium sulfur (Li–S) batteries have been considerably studied in energy storage systems because of their extremely high energy density. Nevertheless, poor sulfur utilization and lower sulfur loading, polysulfides shuttling, and short cycling life are the major obstacles to their application. Herein, we present the cubic structure of CoS2 microcrystals decorated on Co/N-codoped carbon nanofibers (denoted as CSCNC) by an electrospinning technique followed by a hydrothermal process. The Li2S6 catholyte was added in the fibrous CSCNC network as the current free electrode for Li–S batteries, which was used as the positive catalyst to restrain the shuttle effect and facilitate the reaction kinetics. Additionally, CoS2 and Co are dual functional electrocatalysts for facilitating lithium sulfide nucleation onto the surface of CSCNC, thus reduce electrochemical polarization and enhance the specific capacity. This CSCNC@Li2S6 electrode exhibits 877 mAh g–1 capacity retention with sulfur loading of 7.11 mg over 200 cycles and has an average decay of 0.11% per cycle. Additionally, the composite electrode with sulfur loading accomplishes up to 14.22 mg, providing 12.7 mAh of extremely high capacity, which is much higher than that of the carbon-based electrodes for Li–S batteries.

Summary Lithium sulfur batteries have drawled worldwide attention in recent years, which benefit of its high‐density energetic, low cost, and environmental benignity. Nevertheless, the shuttle effect of polysulfides and resulting self‐discharge lead to capacity fade loss and poor electrochemical performance. Herein, graphitic‐carbon nitride/carbon nanotubes (g‐C3N4/CNTs) hybrid membrane is fabricated by the flow‐direct vacuum filtration process. The as‐prepared 3‐D freestanding g‐C3N4/CNTs membrane employed as positive current collector containing Li2S6 catholyte solution for lithium/polysulfides batteries. The fabricated g‐C3N4/CNTs provide a physical barriers and chemisorption resist polysulfide shuttling. Moreover, the conductive network constructed by CNTs can empower sulfur to be evenly distributed in the cathode and accelerates electron transport. Thus, to further prove the cooperative effect of g‐C3N4 and CNTs, the freestanding g‐C3N4/CNTs/Li2S6 electrode exhibits more stable electrochemical performance than CNTs/Li2S6 electrode, deliver the first discharge capacity of 876 mAh g−1 at 0.5 C and maintained at 633 mAh g−1 after 300 cycles. The sulfur mass in electrode was increased to 7.11 mg, and the g‐C3N4/CNTs/Li2S6 electrode also possess a high capacity retention of 75.5%. Meanwhile, g‐C3N4 modified CNTs can not only trap polysulfides by strong adsorption but also effectively inhibit the self‐discharge behavior of lithium/polysulfides batteries. As a consequence, the g‐C3N4/CNTs composites for lithium/polysulfides batteries are indicating an excellent electrochemical stability with a long‐term storage without obvious capacity degradation.

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