水体系自组装法制备钛酸锂纳米负极材料研究  

Self-assembly preparation of Li4Ti5O12 nanomaterial in water system

作　　者：刘梦菁 胡国新[1] Liu Mengjing;Hu Guoxin(School of Mechanical and Power Engineering,Shanghai Jiao Tong University,Shanghai 200240)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《化工新型材料》2020年第3期85-90,共6页New Chemical Materials

基　　金：国家自然科学基金(51676128)。

摘　　要：以偏钛酸粉末作为钛源,制备钛酸锂(Li4Ti5O12)纳米材料,Li4Ti5O12由含锂过氧化钛配合物分解自组装后经煅烧结晶而得。采用X射线衍射、扫描电子显微镜、氮气吸附-脱附和恒流充放电测试对材料结构、形貌和电化学性能进行表征。结果表明:水体系下,锂钛摩尔比为4∶5、于600℃煅烧5h得到的Li4Ti5O12纳米球颗粒粒径在500nm左右,且具有丰富的孔隙,比表面积达到22.947m2/g;在电流密度4000mA/g条件下,比容量为157mAh/g,电流密度500mA/g下循环400次放电容量保持率为95.2%。表明水体系自组装形成的Li4Ti5O12纳米负极材料可以缩短锂离子迁移距离,其多孔性可以增大电解液与电极活性材料的接触面积,使离子电子传输速率同时得到提高,从而获得优异的电化学性能。The lithium titanate(Li4Ti5O12)nanomaterial was prepared by using metatitanic acid powder as a titanium source.Li4Ti5O12 was obtained by decomposing and self-assembling a lithium-containing titanium oxide complex after calcination and crystallization.The structure,morphology and electrochemical properties of the materials were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),nitrogen adsorption desorption(BET),and constant current charge and discharge tests.Under the water system,with the lithium to titanium ratio of 4∶5,lithium titanate nanospheres about 500 nm can be obtained by calcining 5 hours at 600℃,and abundant pores with a specific surface area of 22.947 m2/g were formed.The specific capacity current density was 157 mAh/g at 4000 mA/g and the capacity retention was 95.2% after 400 cycles at 500 mA/g.Therefore,the lithium titanate nanoparticles can shorten the lithium ion migration distance and the porosity can increase the contact area between the electrolyte and the electrode active material,the excellent electrochemical performance were obtained.

关 键 词：锂离子电池 钛酸锂 纳米材料 自组装 电化学性能 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TM912[电气工程—电力电子与电力传动]