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

Abstract

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.