四氧化三锰制备掺杂LiMn_2O_4及其性质研究  

Preparation and Characterization of Doped LiMn_2O_4 Using Mn_3O_4 as Starting Materials

作　　者：于小林[1] 吴显明[1,2] 陈上[1,2] 陈守彬[1] 丁心雄 Yu Xiaolin Wu Xianming Chen Shang Chen Shoubin Drag Xinxiong(College of Chemistry and Chemical Engineering, Jishou University, Jishou 416000 Xiangxi Minerals and New Materials Development and Service Center, Jishou 416000, China)

机构地区：[1]吉首大学化学化工学院,湖南吉首416000 [2]湘西自治州矿产与新材料技术创新服务中心,湖南吉首416000

出　　处：《广东化工》2016年第21期13-14,30,共3页Guangdong Chemical Industry

基　　金：国家自然科学基金项目(21263004)

摘　　要：以Mn3O4、Li2CO3、Co3O4、Al2O3和NiCO_3为原料,固相法合成Co、Al、Ni掺杂LiMn_2O_4。采用X-射线衍射、扫描电子显微镜、恒电流充放电和电化学阻抗等技术研究合成材料的结构、形貌及电化学性能。结果表明:Co、Al、Ni掺杂没有改变LiMn_2O_4的晶体结构,但晶格常数略有减小。掺杂后LiMn_2O_4晶粒规整,表面光滑,晶粒形貌差别不大。掺杂后LiMn_2O_4的比容量有所下降,循环性能得到改善,容量保持率是Li Co0.05Mn1.95O4>Li Ni0.05Mn1.95O4>Li Al0.05Mn1.95O4>LiMn_2O_4。Li Co0.05Mn1.95O4的循环性能最好。掺杂后LiMn_2O_4锂离子扩散系数有所提升,其中Li Co0.05Mn1.95O4的锂离子扩散系最大。Co. Al and Ni doped LiMn2O4 po;vders were prepared by a simple solid state reaction nsing Mn3O4. Li2CO3. Co3O4. Al2O3 and NiCO3 as starting materials. The structure, morphology and electrochemical performance of the prepared powders were studicd by X-ray diffractometry, scanning electron microscopy, galvanostatic charge-discharge test and electrochemical impedance spectroscopy techniques. The results show that Co, AI and Ni doped LiMn2O4 has the same structure and morphology with the undoped LiMn2O4. The specific capacity of doped LiMn2O4 is slightly smaller than LiMn2O4, among the doped LiMn2O4, LiCo0.05Mn1.95O4 shows the best cycling performance. The doped kiMn2O4 has higher Li diffusion coefficient than the undoped one.

关 键 词：锂离子电池 掺杂 锰酸锂 电化学 

分 类 号：TQ137.12[化学工程—无机化工]