Nanocrystalline tin disulfide coating of reduced graphene oxide produced by the peroxostannate deposition route for sodium ion battery anodes

A highly stable sodium ion battery anode was prepared by deposition of hydroperoxostannate on graphene oxide from hydrogen-peroxide-rich solution followed by sulfidization and 300 °C heat treatment. The material was characterized by electron microscopy, powder X-ray diffraction and X-ray photoelectron spectroscopy which showed that the active material is mostly rhombohedral SnS₂ whose (001) planes were preferentially oriented in parallel to the graphene oxide sheets. The material exhibited >610 mA h g^-1 charge capacity at 50 mA g^-1 (with >99.6% charging efficiency) between 0 and 2 V vs. Na/Na⁺ electrode, high cycling stability for over 150 cycles and very good rate performance, >320 mA h g^-1 at 2000 mA g^-1.