摘要
采用水热离子交换法制备钛酸锂纳米棒,用热重法(TG)分析钛酸锂在热处理过程中的重量损失,用X射线衍射仪(XRD)和透射电子显微镜(TEM)测试水热反应温度(150和180℃)和高温热处理(600、750和900℃)对钛酸锂结构的影响,用恒流充放电法和循环伏安法对钛酸锂进行电化学性能评价.结果表明,P25与NaOH在180℃水热反应并经过H+与Li+交换,热处理后可以得到纳米棒状钛酸锂,热处理温度为750℃时,初始放电比容量为164 mAh/g,在电压为1.5V左右有明显的充放电电压平台,50次充放电循环后比容量保持率达98.33%,表现出良好的电化学性能.
Li4Ti5O12 nanorods were prepared by hydrothermal ion exchange method.The weight loss process of Li4Ti5O12 during the heat treatment was studied by thermogravimetric method(TG).The structure and composition of the samples obtained at different hydrothermal temperatures(150℃ and 180℃) and different heat-treatment tempera-tures(600℃,750℃ and 900℃) were characterized by X-ray diffraction(XRD) and transmission electron microscope(TEM).The electrochemical performances were evaluated by means of various techniques including galvanostatic charge/discharge tests and cycle voltammetry(CV) in terms of cycling performance and rate capability.The results in-dicate that Li4Ti5O12 nanorods can be synthesized after hydrothermal reaction at 180℃ by the way of ion exchanges.The first specific discharge capacity of the samples heat-treated at 750℃ is 164 mAh/g with retention ratio of 98.33% after 50 charge-discharge cycling,and the voltage plateau at 1.5V could be seen in the discharge curves distinctively.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第2期123-128,共6页
Journal of Inorganic Materials
基金
国家自然科学基金(50871053)~~
关键词
锂离子电池
纳米棒
钛酸锂
水热离子交换法
lithium ion cell
nanorods
lithium titanate
hydrothermal ion exchange