Co_3O_4纳米线阵列的制备及其储锂性能

利用水热和后热处理的方法,在不锈钢片上制备了Co_3O_4纳米线阵列,并作为阳极应用到锂离子电池上。结构和形貌表征发现,Co_3O_4纳米线为多孔结构,由大小为20~40nm的Co_3O_4颗粒构成。电化学特性测试表明,Co_3O_4纳米线阵列电极具有良好的循环稳定性和优异的倍率特性,在890mA/g的电流密度下,可逆容量为1 300mAh/g,循环150次后,库伦效率保持在99%以上。分析指出,多孔纳米结构不但使活性物质Co_3O_4能够充分与电解液接触并反应,有效地适应材料在充放电过程中的体积变化,而且减小了锂离子和电子在其中的输运距离。同时,在集流体上直接生长活性物质,它们之间具有良好的电接触,有利于电子通过界面的快速传输。

Co3O4 Nanowire Array Preparation and Its Lithium Storage Property

Utilize the methods of hydrothermal and after-heat treatment to prepare the Co3 O4 nanowire array on the stainless steel sheet and apply it in the lithium ion battery as positive pole.The structure and morphology characterization shows that the Co3 O4 nanowire is porous structure and it is constituted by the Co3O4 particles which dimension is 20～40 nm.The electrochemical properties test shows that the Co3O4 nanowire array has excellent cycling stability and outstanding ratio characteristics,the reversible capacity is 1 300 mAh/g under the current density of 890 mA/g,the coulombic efficiency can be maintained at over 99％ after 150 times circulation.The analysis indicates that the porous nano structure not only make the active material Co3O4 to sufficiently contact with electrolyte and react and efficient adapt the volumetric change of material during the charge-discharge process,but also reduce the transport distance of lithium ion and electron inside it.At the same time,the active material will direct grow in the current collector,good electrical contact is existed between them which is beneficial to rapid transport of electron passing through the interface.