Hollow Multishelled Heterostructured Anatase/TiO₂ (B) with Superior Rate Capability and Cycling Performance

TiO₂ is a potential anode material for lithium-ion batteries due to its high rate capability and high safety. Here, a controllable synthesis for hollow nanostructured TiO₂ , with heterostructured shells of TiO₂ (B) and anatase phases, is presented for the first time, by using a sequential templating approach. The hollow nanostructures can be easily controlled to produce core-shell and double-shelled materials with different compositional ratios of anatase to TiO₂ (B) by tuning the synthetic conditions. When used as the anode materials for lithium-ion batteries, a specific discharge capacity of 215.4 mAh g^-1 for the double-shelled anatase/TiO₂ (B) hollow microspheres is achieved at a current rate of 1 C (335 mA g^-1 ) for the 100th cycle and shows high specific discharge capacities of 141.6 and 125.7 mAh g^-1 at the high rates of 10 and 20 C over 1000 cycles. These results are due to the unique stable hollow multishelled structure, which has a high specific surface area, as well as the interface between the heterostructured anatase/TiO₂ (B) phases contributing a substantial number of lithium-ion storage sites.