Constructing hierarchical submicrotubes from interconnected TiO2 nanocrystals for high reversible capacity and long-life lithium-ion batteries

Abstract

Here, we report a facile hydrothermal approach for synthesizing anatase TiO2 hierarchical mesoporous submicrotubes (ATHMSs) with the aid of long-chain polymer as soft template. The TiO2 nanocrystals, with sizes of 6-8 nm, are well interconnected with each other to build tubular architectures with diameters of 0.3-1.5 μ1/4m and lengths of 10-25 μ1/4m. Such highly porous structures give rise to very large specific surface area of 201.9 m2 g -1 and 136.8 m2 g -1 for the as-prepared and annealed samples, respectively. By using structurally stable ATHMSs as anode materials for lithium-ion batteries, they exhibited high reversible capacity, long cycling life and excellent cycling stability. Even after 1000 cycles, such ATHMS electrodes retained a reversible discharge capacity as high as 150 mAh g-1 at the current density of 1700 mA g-1, maintaining 92% of the initial discharge capacity (163 mAh g-1).