WS2 nanoplates embedded in graphitic carbon nanotubes with excellent electrochemical performance for lithium and sodium storage

Abstract

WS2 has been considered as a promising anode material due to its high lithium storage capacity as well as fascinating physical properties. However, the insufficient electrical and ionic conductivities deteriorate the rate performance of the batteries. Herein, we report a simple synthetic approach towards graphene-WS2 hybrids by rolling graphene into a hollow nanotube in which WS2 nanoplates are encapsulated. This new electrode design strategy facilitates the fabrication of integrated and binder-free lithium ion battery and sodium ion battery electrodes by combining electrospinning and chemical vapor deposition (CVD) methods. Benefiting from their confined growth and the interconnected in-situ graphitic carbon coating nanocable web, the WS2@G with nano-level WS2 dispersion not only provides an efficiently conductive and electrolyte accessible framework, but effectively alleviates the volume change during the cycling, enabling a mechanically robust binder-free electrode along with the outstanding electrochemical Li+ and Na+ storage properties.