Improved Lithium-Ion and Sodium-Ion Storage Properties from Few-Layered WS Nanosheets Embedded in a Mesoporous CMK-3 Matrix.

An integrated WS @CMK-3 nanocomposite has been prepared by a one-step hydrothermal method and then used as the anode material for lithium-ion and sodium-ion batteries. Ultrathin WS nanosheets have been successfully embedded into the ordered mesoporous carbon (CMK-3) framework. Owing to the few-layered nanostructure of WS , as well as the high electronic conductivity and the volume confinement effect of CMK-3, the material shows larger discharge capacity, better rate capability, and improved cycle stability than pristine WS . When tested in lithium-ion batteries, the material delivers a reversible capacity of 720 mA h g after 100 cycles at a current density of 100 mA g . A large discharge capacity of 307 mA h g is obtained at a current density of 2 A g . When used in sodium-ion batteries, the material exhibits a capacity of 333 mA h g at 100 mA g without capacity fading after 70 cycles. A discharge capacity of 230 mA h g is obtained at 2 A g . This excellent performance demonstrates that the WS @CMK-3 nanocomposite has great potential as a high-performance anode material for next-generation rechargeable batteries.