Polar mesoporous zinc sulfide nanosheets encapsulated in reduced graphene oxide three-dimensional foams for sulfur host

Lithium-sulfur (Li-S) batteries exhibit the high specific capacity and energy density, but prevented by the low coulombic efficiency and weak cycle life. Herein, we fabricate reduced graphene oxide (r-GO) three-dimensional (3D) foams encapsulating polar mesoporous zinc sulfide (ZnS) nanosheets and subsequently utilize the ZnS/r-GO foams to load sulfur (ZnS/r-GO/S) as cathodes for improving the performance of Li-S batteries. The mesoporous diameter of the ZnS nanosheets is approximately 10 similar to 30 nm and lots of pores in the 3D foams are observed. The porous structure provides abundant sites to adsorb and accommodate sulfur species. The cathode of the ZnS/r-GO/S exhibits 1259 mA h g(-1) of initial capacity and 971.9 mA h g(-1) of the reversible capacity after 200 cycles at 0.1C (1C = 1675 mA g(-1)). At 1 C, it still exhibits the tiny capacity decay rate of 0.019% per cycle after 300 cycles. This work may be adopted to combine the nonpolar and polar materials as a 3D network structure for high-performance Li-S batteries.