Flaky CoS2 and graphene nanocomposite anode materials for sodium-ion batteries with improved performance

A flaky CoS2 based reduced graphene oxide (CoS2/rGO) composite was successfully synthesized via a solvothermal route. CoS2 nanoparticles with sizes of 20-30 nm are uniformly anchored on the reduced graphene oxide (rGO), resulting in the flaky structure. The as-fabricated CoS2 based rGO composite exhibits improved sodium storage capacity compared with bare CoS2 as anode materials for sodium-ion batteries. After cycling for 1000 cycles at 1 A g(-1), the CoS2 based rGO electrode still delivered a reversible capacity of 192 mA h g(-1). The enhanced electrochemical performances of the CoS2 based rGO composite can be ascribed to the formation of a robust, conductive and high surface area composite.