Preparation of zinc sulfide@reduced graphene oxide nanocomposites with enhanced energy storage performance

Abstract

Zinc sulfide@reduced graphene oxide composites with a three-dimensional (3D) network-like framework were prepared through a simple solvothermal reaction. Numerous ultrasmall ZnS nanoparticles make up the composites with being well attached on both sides of reduced graphene oxide. The ZnS@reduced graphene oxide nanocomposites show remarkable electrochemical behaviors for lithium-ion batteries as anode materials. They deliver an outstanding specific capacity of 1130.5 mAh g−1 at 100 mA g−1 after 200 cycles. Reversible specific capacities of 480.9 mAh g−1 and 742.7 mAh g−1 can be maintained at 1000 mA g−1 as well as 2000 mA g−1, respectively. The outstanding electrochemical performance is mainly ascribed to the reduced graphene oxide in the nanocomposites. The 3D network-like framework could provide a high surface area with numerous active sites. It not only promotes the fast diffusion of the electrons and ions, but effectively accommodates the volume-expansion during the lithium ion insertion/extraction process. Thus, the superior electrochemical performance enables the nanocomposites to be a desirable anode for lithium ions battery in the coming years.