Ultrafine SnO2 nanoparticles decorated onto graphene for high performance lithium storage

Ultrafine SnO2 nanoparticles of 2-5 nm are controllably synthesized onto the surface of graphene via a simple one-pot hydrothermal approach without the addition of a surfactant. The resulting SnO2-graphene nanocomposite shows a high level of homogeneous dispersion and high content of nanosized SnO2 (85%) loading. Such unique features of the SnO2-graphene nanocomposite can not only buffer efficiently the volume change of SnO2 during charge-discharge processes, but also facilitate fast diffusion of lithium ions in SnO2 and the transport of electrons in graphene when it is used as an anode material for lithium storage. As a result, the ultrafine SnO2-graphene nanocomposite exhibits a very high reversible capacity of 1037 mA h g(-1), excellent capacity retention of 90% over 150 cycles, and good high-rate capability. Combined with the other advantages of easy synthesis, low-cost, environment friendliness and high yield, the SnO2-graphene nanocomposite could be a promising anode material for lithium ion batteries.