Freeze-dried WS2 composites with low content of graphene as high-rate lithium storage materials

Few layered WS2-graphene nanosheet composites are prepared by a simple and scalable hydrothermal reaction and a subsequent freeze-drying method. The freeze-dried WS2-graphene composite exhibits good cycling stability and outstanding high-rate capability of lithium storage. The reversible capacity remains 647 mA h g(-1) after 80 cycles at a current density of 0.35 A g(-1). Comparable capacities of 541 and 296 mA h g(-1) can still be maintained when cycling at even higher current densities of 7 and 14 A g(-1) (7 and 14 mA cm(-2)) respectively.