Enhanced Lithium Storage Performance of Liquid-Phase Exfoliated Graphene Supported WS2 Heterojunctions

To improve the electrical conductivity and the cycling stability of layered transition metal disulfides (TMDs) as lithium-ion battery anode, graphene@WS2 heterojunction composites are prepared by a facile one-pot process, involving liquid-phase exfoliation of graphene in N-methylpyrrolidone, followed by in-situ growth of WS2 in the graphene dispersion induced by a microwave-assisted solvothermal method. The liquid-phase exfoliated graphene (LEGr) with exceptional atomic structure not only serves as a substrate to couple WS2, but also serves as a mini-current collector for the rapid transport of electrons within the anode. The LEGr-based heterojunction WS2 composites exhibit improved lithium storage performance compared to the counterpart based on graphene oxide (GO), including higher lithium storage capacity, superior rate capability and outstanding cycling stability. This protocol enables processing and construction of advanced TMD heterojunction electrodes based on LEGr using an economical pathway.