Abstract
In our work, anatase TiO2 nanostructures on Ti foil transformed from sodium titanate were synthesized by a facile hydrothermal reaction. Under different hydrothermal conditions, diverse morphologies including nanowire, nanosheet and nanobelt can be obtained. The rate of sodium ion intercalating into TiO6 structure during the hydrothermal reaction will influence the morphology of sodium titanate. High intercalation rate occurring at high temperature and high sodium ion concentration environment leads to the formation of nanowire TiO2. On the contrary, lamellar TiO2 including nanosheet and nanobelt were obtained in low intercalation rate condition. Anatase TiO2 on conductive Ti foil can be used as a binder-free anode material for lithium ion batteries. Nanowire exhibits the best lithium ion batteries performance among three different morphologies and retains 220.95 mAh/g after 100 cycles at the rate of 1 C (335 mA/g). In variable current test, at the rate of 20 C (6.7 A/g), anatase TiO2 nanowire still remains 99.04 mAh/g. The extraordinary performance can be attributed to high specific surface area and low charge transfer resistance. This result suggests that anatase TiO2 growing on Ti foil can be a promising candidate for high performance lithium ion batteries.