Preparation and electrochemical properties of graphene-supported Si-TiO2 nanospheres as anode material for Li-ion batteries

Graphene-supported Si-TiO2 (Si-Ti-GE) composites have been synthesized by a simple polymerization and sintering method. In the Si-Ti-GE composites, many small Si-TiO2 particles are scattered on the graphene sheet, which can mitigate the agglomeration of the material and further reduce the particle size. The initial discharge capacities of Si-TiO2, Si-Ti-GE-1, Si-Ti-GE-2, and Si-Ti-GE-3 are 336.9, 337.2, 339.8, and 356.6mAh g(-1) at the current density of 200mAg(-1), respectively. The discharge rate capacities of TiO2, Si-TiO2, and Si-Ti-GE-3 composites retain 57.5%, 41.7%, and 82.1% at the current density from 100 to 400mAg(-1), respectively. Therefore, the introduction of graphene not only could facilitate the Li+ diffusion and electron transport but also could make better electrical conductivity.