Mesoporous anatase TiO2 nanorods as thermally robust anode materials for Li-ion batteries: detailed insight into the formation mechanism.

Uniformly mesoporous and thermally robust anatase nanorods were produced with quantitative yield by a simple and efficient one-step approach. The mechanism of this process was revealed by insertion of Eu(3+) cations from the reaction medium as luminescent probes. The obtained structure displays an unusually high porosity, an active surface area of about 300 m(2) g(-1) and a specific capacity of 167 mA h g(-1) at a C/3 rate, making it attractive as an anode electrode for Li-ion batteries. An additional attractive feature is its remarkable thermal stability; heating to 400 °C results in a decrease in the active surface area to a still relatively high value of 110 m(2) g(-1) with conservation of open mesoporosity. Thermal treatment at 800 °C or higher, however, causes transformation into a non-porous rutile monolith, as commonly observed with nanoscale titania.