Abstract:Compound Zn₂Sn_0.8Ti_0.2O₄ was synthesized by a hydrothermal method in which SnCl₄·5H₂O, TiCl₄, ZnCl₂ and N₂H₄·H₂O were used as reactants. The composite Zn₂Sn_0.8Ti_0.2O₄/C was then prepared through a carbothermic reduction process using the as-prepared Zn₂Sn_0.8Ti_0.2O₄ and glucose as reactants. The structure, morphology and electrochemical properties of the as-prepared products were investigated by XRD, XPS, TEM and electrochemical measurements. In addition, electrochemical Li insertion/extraction in composite Zn₂Sn_0.8Ti_0.2O₄/C were examined by ex situ XRD and SEM. The first discharge capacity of Zn₂SnO₄ is about 1670.8 mA·h/g, with a capacity retain of 342.7 mA·h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05−3.0 V. Comparing with the Zn₂SnO₄, some improved electrochemical properties are obtained for Zn₂Sn_0.8Ti_0.2O₄, Zn₂SnO₄/C and Zn₂Sn_0.8Ti_0.2O₄/C. The composite Zn₂Sn_0.8Ti_0.2O₄/C shows the best electrochemical properties, and its first discharge capacity is about 1530.0 mA·h/g, with a capacity retain of 479.1 mA·h/g the 100th cycle.

Key words: Zn₂SnO₄; Zn₂Sn_0.8Ti_0.2O₄/C; titanium substitution; lithium ion batteries; anode materials