Solvothermal synthesis of hedgehog-like mesoporous rutile TiO2 with improved lithium storage properties

Hedgehog-like mesoporous rutile TiO2 (HLR-TiO2) composed of well-defined nanoneedles is fabricated in a solvothermal system containing tetrabutyl titanate, hydrochloric acid aqueous solution and diethylene glycol with a proper volume ratio. A possible formation mechanism of the HLR-TiO2 is proposed on the basis of different experimental results and three different morphologies are obtained by changing the solvent with other conditions unchanged. Given its unique hierarchical mesoporous nanostructures, the HLR-TiO2 shows superior lithium storage properties with excellent discharge specific capacity of 243.3 mA h g−1 obtained after 100 cycles at a current rate of 1 C among the three samples, which is almost unparalleled to other rutile TiO2-based electrodes. In particular, a specific capacity of 80.2 mA h g−1 is still maintained after 2000 cycles even at a high current rate of 20 C, indicating that great potential of HLR-TiO2 as an electrode material for lithium-ion batteries (LIBs).