文献类型：期刊文献

中文题名：纳米LiCo_xMn_(2-x)O_4粉体的制备与电化学性能

英文题名：Synthesis and electrochemical properties of LiCo_xMn_(2-x)O_4 nano-powder

作者：蔡羽[1];赵胜利[2];文九巴[2];赵崇军[3]

机构：[1]河南科技大学信息管理研究所,河南洛阳471003;[2]河南科技大学材料学院,河南洛阳471003;[3]华东理工大学材料学院,上海200237

年份：2009

卷号：40

期号：2

起止页码：338

中文期刊名：功能材料

外文期刊名：Journal of Functional Materials

收录：CSTPCD;;EI(收录号：20091211965999);Scopus;北大核心:【北大核心2008】；CSCD:【CSCD2011_2012】；

基金：国家自然科学基金资助项目(20504026);河南科技大学人才科研基金资助项目(04015)

语种：中文

中文关键词：纳米粉体;LiCoxMn2-xO4;溶胶-凝胶;PAA;掺杂

外文关键词：nano-powder; LiCoxMn2-xO4; sol-gel; PAA; doping

摘要：采用溶胶-凝胶法并结合热处理工艺制备LiCoxMn2-xO4粉体，结合热处理工艺制备LiCoxMn2-xO4粉体。利用热重-差热分析、X射线衍射、透射电镜、充放电测试等方法对前驱体的热分解行为、粉体的结构、形貌及电化学性质进行了表征，同时研究了钴掺杂量对其结构和电化学性能的影响。结果表明，直接以聚丙烯酸（PAA）为螯合剂合成了稳定的溶胶和凝胶，进一步获得了粒径分布均匀、无团聚的尖晶石LiCoxMn2-xO4纳米粉体。随着钴掺杂量的增加，晶格常数、晶粒尺寸逐渐减小，晶格畸变逐渐增大，但对尖晶石结构影响较小LiCoxMn2-xO4粉体的放电比容量随着x值增大略有降低，但循环性能得到明显的改善。在电流密度0．1mA／cm^2、截止电压3．5～4．3V时，粒径约80nm的LiCo0.1Mn1.9O4粉体首次放电比容量达135mAh／g，20次循环后的稳定放电比容量为118mAh／g，且每次容量衰减低于0．2％，具有较好的电化学性能。
Spinel LiCoxMn2-xO4 powders were prepared via sol-gel combined with heating treatment process. The thermal decomposition behavior of gel precursor, structure, morphology and electrochemical properties of LiCoxMn2-xO4 powders were characterized by thermogravimetric/differential scanning calorimetry （TG-DSC）,X-ray diffraction （XRD） ,transmission electron microscopy （TEM） and constant current charge/discharge technologies. The effect of Co-dopant on its structure and electrochemical properties was also investigated. The results show that the stable sol and gel are synthesized using polymer polyacrylic acid （PAA） as the chelator and the cubic spinel structure LiCoxMn2-xO4 nano-powders with uniform distribution of particle size and no distinct aggregation are further obtained. The lattice constant and crystal size of LiCoxMn2-xO4 powder decrease and the crystal aberrance increase with the increase of cobalt content but doping Co has less effect on its structure. The initial discharge special capacity of LiCoxMn2-xO4 slightly decreases with the increasing content of Co but its cyclic performance is improved obviously resulting from the enhancement of structure stability. The LiCo0.1Mn1.9O4 powder consisted of about 80nm particle size, which possesses the initial and stable discharge capacity of 135mAh/g and 118mAh/g and 〈0.2% capacity fading after 20 cycles at the current density of 0. 1mA/ cm^2 and cut-off voltage of 3.5-4.3V,exhibits superior electrochemical properties.