Flower-like SnO2 nanoparticles grown on graphene as anode materials for lithium-ion batteries

Abstract

Tin oxide (SnO2)/graphene composite was synthesized from SnCl2 · 2H2O and graphene oxide (GO) by a wet chemical-hydrothermal route. The GO was reduced to graphene nanosheet (GNS) and flower-like SnO2 nano-crystals with size about 40 nm were homogeneously distributed on the surface of GNS. The SnO2/graphene composites delivered a superior first discharge capacity of 1941.9 mAhg−1 with a reversible capacity of 901.7 mAhg−1 at the current density of 100 mAg−1. Moreover, even at higher densities of 200 and 500 mAg−1, the SnO2/graphene composite still maintained enhanced cycling stability. After 40 cycles, the discharge capacity was still maintained at 691.1 mAhg−1 at the current density of 100 mAg−1. The SnO2/graphene composite displayed an outstanding Li-battery performance with large reversible capacity and enhanced rate performance, which can be attributed to the highly uniform distribution of SnO2 nanoparticles and high reduction degree of graphene. This result strongly indicates that the SnO2/graphene composite was a promising anode material in high-performance lithium-ion batteries.