A SnO2/graphene composite as a high stability electrode for lithium ion batteries

A simple solution-based synthesis route, based on an oxidation–reduction reaction between graphene oxide and SnCl2
• 2H2O, has been developed to produce a SnO2/graphene composite. In the prepared composite, crystalline SnO2 nanoparticles with sizes of 3–5 nm uniformly clung to the graphene matrix. When used as an electrode material for lithium ion batteries, the composite presented excellent rate performance and high cyclic stability. The effect of SnO2/graphene ratio on electrochemical performance has been investigated. It was found that the optimum molar ratio of SnO2/graphene was about 3.2:1, corresponding to 2.4 wt.% of graphene. The composite could deliver a charge capacity of 840 mAh/g (with capacity retention of 86%) after 30 charge/discharge cycles at a current density of 67 mA/g, and it could retain a charge capacity of about 590 and 270 mAh/g after 50 cycles at the current density of 400 and 1000 mA/g, respectively.