High-Performance Mos2 Quantum Dots/Graphene Functionalized Separator and its Failure Analysis Under High Sulfur Loading

•An ultralight MoS2 QDs-NRGO composites modified separator is designed for Li-S batteries.•The synergistic inhibitory effect of MoS2 QDs-NRGO can effectively inhibit LiPSs shuttle.•Under high sulfur loading, the inhomogeneous deposition of Li2S in the separator will blocked the lithium-ion diffusion.•An appropriate thickness of the modified coating layer can mitigate the capacity decline under high sulfur loading.