MnO2-decorated graphene aerogel with dual-polymer interpenetrating network as an efficient hybrid host for Li-S batteries

Abstract A hybrid host combined with rigid and flexible structural moieties to confine sulfur species physically and chemically is designed and applied for the lithium-sulfur battery. The self-assembled graphene aerogel with nano-MnO 2 modified walls serves as the rigid sulfur container while the cross-linked PVP-PVA interpenetrating network acts as the flexible polysulfide trap. The synergic actions enable the hybrid host to present not only good electronic and ionic 3D transfer pathways, but also superior physical and chemical sulfur confinement. Consequently, the MGPP@S composite cathode exhibits excellent electrochemical energy storage performance. It shows initial discharge capacity of 1492, 1054, 833, 659 mAh g −1 at 0.1C, 0.2C, 0.5C, 1C, respectively; meantime it retains a capacity over 755 mAh g −1 during 250 cycles at 0.2C and only has 0.06% capacity decay per cycle during 500 cycles at 1C. The major capacity decay on first several cycling is accounted for sulfurous consumption in saturating the electrolyte and building the interfacial layer; afterwards, the composite electrode can perform consistent capability upon extending cycling.