Nanocrystalline Ti2/3Sn1/3O2 as anode material for Li-ion batteries

We prepared nanocrystalline Ti2/3Sn1/3O2 by a coprecipitation method starting from Ti(isopropoxide)4 and SnCl4·5H2O followed by calcination at 600 °C. TEM and XRD measurements reveal crystallite sizes of about 5 nm and a crystal structure equivalent to those of TiO2 rutile and SnO2 cassiterite. The local structure was investigated with 119Sn NMR and Sn Mössbauer spectroscopy. The material was cycled with C/20 at voltages between 3.0 and 0.02 V against Li metal. Specific capacities of 300 mAh g−1 were obtained for 100 cycles with voltage profiles very similar to those of pure SnO2. Faster cycling leads to strong decrease of the capacities but after returning to C/20 the initial values are obtained.

► Coprecipitation method to prepare solid solution Ti2/3Sn1/3O2 as anode material for Li-ion batteries. ► Nanocrystalline material with narrow crystallite size distributrion around 5 nm. ► Good cycling stability in Li batteries with specific capacities of 300 mAh g−1 for 100 cycles.