LAUSR

Abstract To improve the performance of anatase TiO 2 as an anode material for sodium-ion batteries, Zn 2+ -doped TiO 2 /C composites are synthesized by a co-precipitation method. The results of XRD, EPR and XPS demonstrate that Zn 2+ occupies at the Ti 4+ site of TiO 2 to form a solid-solution, resulting in an expansion of lattice and an increase of Ti 3+ content. The expansion of lattice can enhance the stability of the crystal structure of TiO 2 . The increase of Ti 3+ content can improve the conductivity of TiO 2 . Therefore, Ti 0.94 Zn 0.06 O 2 /C delivers a reversible capacity of 160 mA h g −1 with a capacity retention of 96% after 100 cycles at 5 C. Even charged/discharged at 10 C, this sample still exhibits a reversible capacity of 117 mA h g −1 , comparing to 86 mA h g −1 for TiO 2 /C. The enhanced electrochemical performances can be ascribed to the improvement of the conductivity and the structural stability of TiO 2 due to Zn 2+ -doping. Therefore, Ti 0.94 Zn 0.06 O 2 /C is an attractive anode material of sodium-ion batteries.