TiO2 hollow spheres on reduced graphene oxide with high rate performance as anodes for lithium-ion batteries†
Abstract
Anatase TiO2 anchored on graphene oxide (GO) can be synthesized through a one-step hydrothermal method. The as-formed nanohybrid has a unique hollow structure and a large surface area. More importantly, compared to the pristine TiO2 counterpart, TiO2@RGO composite materials as anodes in lithium-ion batteries have demonstrated a uniform and highly crystallized morphology and exhibited excellent cycling stability and rate capability of 352 mA h g−1 at 0.5C and 223 mA h g−1 at 5C after 100 cycles, indicating that the TiO2@RGO nanocomposite has promise in advanced Li-ion batteries. The improvement of electrochemical performance is assigned to the enhanced conductivity in the presence of GO in the TiO2@RGO nanocomposite, the anatase and TiO2–B mixed crystal phase of the hollow sphere TiO2@RGO nanocomposite, the small size of TiO2 particles in the nanocomposite, and the enlarged electrode/electrolyte contact area, leading to more active sites in TiO2@RGO.