Solvothermal ion exchange synthesis of ternary cubic phase Zn2Ti3O8 solid spheres as superior anodes for lithium ion batteries

A rational strategy for the synthesis of ternary cubic phase Zn 2 Ti 3 O 8 solid spheres has been developed for application in lithium ion batteries . In this process, titanium glycolate solid spheres are used as nanostructure template and titanium source, whose functional groups are replaced by zinc ions through a solvothermal ion exchange method in accordance with the Zn/Ti atomic ratio of 2:3. When adjusting the Zn/Ti atomic ratios to 0:3, 1:3, the anatase TiO 2 solid spheres and multiphase complex of TiO 2 /ZnTiO 3 solid spheres can be obtained. However, with the increasing of Zn/Ti atomic ratio to 3:3, in addition of cubic phase Zn 2 Ti 3 O 8 solid spheres, a lot of hexagonal ZnO nanoparticles are synthesized. As anodes for lithium ion batteries, the delivered capacities of Zn 2 Ti 3 O 8 solid spheres are higher than those of TiO 2 and TiO 2 /ZnTiO 3 solid spheres at 300 mA g −1 . Notably, the high purity cubic phase Zn 2 Ti 3 O 8 solid spheres can still release a reversible capacity of 146.7 mAh g −1 even at 2000 mA g −1 over 1000 cycles. Also, the Zn 2 Ti 3 O 8 solid spheres show a good electrochemical performance in the full cells. The superior electrochemical properties are ascribed to the favorable crystal structure and highly developed porous structure of Zn 2 Ti 3 O 8 solid spheres.