Sn-Doped Rutile TiO₂ Hollow Nanocrystals with Enhanced Lithium-Ion Batteries Performance

Hollow structures and doping of rutile TiO₂ are generally believed to be effective ways to enhance the performance of lithium-ion batteries. Herein, uniformly distributed Sn-doped rutile TiO₂ hollow nanocrystals have been synthesized by a simple template-free hydrothermal method. A topotactic transformation mechanism of solid TiOF₂ precursor is proposed to illustrate the formation of rutile TiO₂ hollow nanocrystals. Then, the Sn-doped rutile TiO₂ hollow nanocrystals are calcined and tested as anode in the lithium-ion battery. They deliver a highly reversible specific capacity of 251.3 mA h g^-1 at 0.1 A g^-1 and retain ∼110 mA h g^-1 after 500 cycles at a high current rate 5 A g^-1 (30 C), which is much higher than most of the reported work.