Facile synthesis of SnO2 nanoparticles dispersed nitrogen doped graphene anode material for ultrahigh capacity lithium ion battery applications

We report a facile strategy to synthesize SnO2 nanoparticles dispersed nitrogen doped graphene (SnO2/NG). Nitrogen doping of graphene was carried out by the pyrolysis of polypyrrole coated poly(sodium 4-styrenesulfonate) functionalized graphene. The SnO2 nanoparticles are dispersed over nitrogen doped graphene by a modified polyol reduction method. The dispersed SnO2 nanoparticles are 2-3 nm in size with homogeneous dispersion and good crystallinity. The SnO2/NG as an anode material in Li ion batteries displays superior reversible capacity, very good rate capability and excellent cyclic performance (1220 mA h g(-1) after 100th cycle). The impedance measurements show that nitrogen doping can significantly reduce the charge transfer resistance of graphene based electrodes. The factors contributing to the excellent electrochemical performance of the SnO2/NG anode material is discussed. The present work opens a new pathway for the development of metal or metal oxide nanoparticle-nitrogen doped carbon nano-structure based nanocomposites for high performance electrochemical energy devices.