Synthesis and electrochemical properties of Zn2SnO4 and Zn2Sn0.8Ti0.2O4/C
(School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China)
Abstract: Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4·5H2O, TiCl4, ZnCl2 and N2H4·H2O were used as reactants. The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 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 Zn2Sn0.8Ti0.2O4/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 Zn2Sn0.8Ti0.2O4, Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C. The composite Zn2Sn0.8Ti0.2O4/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; Zn2Sn0.8Ti0.2O4/C; titanium substitution; lithium ion batteries; anode materials