Interface-engineered tin disulfide and reduced graphene oxide dual coupled hybrid as a binder free current collector for confinement and catalytic conversion of lithium polysulfides in lithium sulfur batteries.

The advanced lithium-sulfur (LiS) batteries are hindered by lithium polysulfides (LiPSs) shuttling. Herein, a flexible self-supporting hybrid current collector dual coupled with reduced graphene oxide (rGO) nanosheets and tin disulfide (SnS2) nanoparticles is rationally constructed via facile hydrothermal and pyrolysis. Aside from generating a three-dimensional (3D) conductive framework, this current collector provides plentiful active sites conducive to sulfur loading. The intimate coupling of polar SnS2, high conductive rGO and robust carbon foam skeleton builds a good interfacial engineering to enhance electron transport and charge transfer across the solid-liquid interface, thereby promoting catalytic transformation of LiPSs adsorbed on the carbon hybrid. Additionally, the SnS2 nanoparticles and nitrogen heteroatoms in situ doped endow LiPSs with a strong synergetic confinement. Consequently, the optimized cathode exhibits a high initial capacity (1147.7 mAh g-1 at 0.2C), excellent rate performance (535.7 mAh g-1 at 3.0C) and an exceptionally low 0.04% capacity decay per cycle over 500 cycles at 2.0C. Notably, a 6.3 mAh cm-2 areal capacity is attained under harsh high-loading (10.0 mg cm-2) and lean-electrolyte (4.4 μL mg-1) conditions. The freestanding architecture also enables flexible pouch-cell operation under repeated bending. These results demonstrate that coupling conductive transport pathways with polar adsorption and catalytic interfaces is an effective strategy for regulating polysulfide chemistry in high-loading LiS batteries.