溶胶凝胶-微波烧结法制备Li_(2)ZnTi_(3)O_(8)及其电化学性能研究

Preparation of Li_(2)ZnTi_(3)O_(8) by Microwave Sintering Combined with Sol-Gel Method and Its Electrochemical Performance

以纳米二氧化钛(TiO_(2))为钛源、无水乙酸锂(CH_(3)COOLi)为锂源、二水合乙酸锌(Zn(CH_(3)COO)_(2)·2H_(2)O)为锌源,采用独特的微波烧结结合溶胶凝胶法在650℃、750℃和850℃条件下制备了钛酸锌锂(Li_(2)ZnTi_(3)O_(8),LZTO)负极材料LZTO-650、LZTO-750和LZTO-850。通过X射线衍射试验对样品结构进行分析,通过扫描电子显微镜对材料的形貌进行表征。在充满氩气的手套箱内组装CR2032纽扣电池并对其电化学性能进行测试。结果表明,LZTO-750在200 mA·g^(-1)电流密度下循环100次后的放电比容量达到277.9 mA·h·g^(-1),在不同电流密度下的倍率性能也有效地得到了改善。因此,采用独特的微波烧结结合溶胶凝胶的方法在750℃的烧结温度下制备的LZTO-750具有优异的倍率性能,为其在锂离子电池中的应用奠定了坚实的基础。

Lithium zinc titanate(Li_(2)ZnTi_(3)O_(8),LZTO)anode materials named LZTO-650,LZTO-750 and LZTO-850 are prepared by a unique microwave sintering combined with sol-gel method under the conditions of 650℃,750℃and 850℃,respectively,using nano-titanium dioxide(TiO_(2))as the titanium source,anhydrous lithium acetate(CH_(3)COOLi)as the lithium source,and zinc acetate dihydrate(Zn(CH_(3)COO)_(2)·2H_(2)O)as the zinc source.The structure of materials is analyzed by using the X-ray diffraction experiments,and the morphology of the materials is characterized by the scanning electron microscope.The CR2032 coin cells are prepared in an Arfilled glovebox,and the electrochemical properties is tested as well.The results show that the discharge specific capacity of LZTO-750 is 277.9 mA·h·g^(-1) after 100 cycles at the current density of 200 mA·g^(-1),and the rate performance is also effectively improved at different current densities.Therefore,the LZTO-750 prepared by using the unique microwave sintering combined with sol-gel method at a sintering temperature of 750℃exhibits an excellent rate performance,making a solid foundation for its application in lithium-ion batteries.