Anatase/rutile titania anchored carbon nanotube porous nanocomposites as superior anodes for lithium ion batteries

Abstract

Anatase/rutile titania anchored carbon nanotube (TiO₂@CNT) porous nanocomposites are fabricated using TiCl₃ and polymer nanotubes as the titanium and carbon sources, respectively, by a hydrothermal process with subsequent heat treatment. As anodes for lithium ion batteries, the electrochemical performance of the nanocomposites is highly dependent on the crystal phase and content of TiO₂. Compared with anatase TiO₂/C nanocomposites, the TiO₂@CNT nanocomposites exhibit high reversible capacity, excellent rate capability and superior long-term cycling stability at high current densities. The enhanced electrochemical performance of the nanocomposites results from the shortened Li⁺ diffusion distance, large contact surface area and sufficient conductivity. In addition, the crystal interface effect of mixed-phase TiO₂ could improve the dispersion rate of electrons, which is conducive to the rapid transport of Li⁺ and the electrons.