TiO2 Hollow Spheres With Flower-Like SnO2 Shell as Anodes for Lithium-Ion Batteries

Abstract

SnO 2 is a promising anode material for lithium-ion batteries due to its high theoretical specific capacity and low operation voltage. However, its poor cycling performance hinders its commercial application. In order to improve the cycling stability of SnO 2 electrodes, novel flower-like SnO 2 /TiO 2 hollow spheres were prepared by facile hydrothermal method using carbon spheres as templates. Their flower-like shell and mesoporous structure highlighted a large specific surface area and excellent ion migration performance. Their TiO 2 hollow sphere matrix and 2D SnO 2 nano-flakes ensured good cycle stability. The electrochemical measurements indicated that novel flower-like SnO 2 /TiO 2 hollow spheres delivered a high specific capacity, low irreversible capacity loss and superior rate performance. After 1,000 cycles at current densities of 200 mA g −1 , the capacity of the flower-like SnO 2 /TiO 2 hollow spheres was still maintained at 720 mAh g −1 . Their rate capacity reached 486 mAh g −1 when the current densities gradually increase to 2,000 mA g −1 .