摘要
常压回流法制备掺杂钴离子的钙锰矿,X-射线衍射(XRD)、热重(TG)、化学分析等测试表明:钙锰矿均为单一相,组成为MgxCoyMnOz·nH2O,其中0.18≤x≤0.22、0≤y≤0.24、2.10≤z≤2.53、0.35≤n≤0.73.以掺钴钙锰矿作锂离子二次电池正极材料,组成为Tod-Co10%(10%Co的Mg0.18Co0.12MnO2.19·0.45H2O)电极放电性能最佳,其首次放电比容量为219mAh/g,100次循环充放电仍有102mAh/g.对比之下,未掺钴的Tod-Co0%电极(钙锰矿)首次放电比容量为211mAh/g,30次循环后为37mAh/g.
Cobalt-doped todorokites were prepared by refluxing at atmospheric pressure, and then charactered by X-ray diffraction （XRD） , thermogravimetry （TG） and the analysis of chemical compositions. These measurements showed that all of the refluxing products were single phase of todorokites and the structure formulas were Mg, CoyMnOx.nH2O,where 0.18 ≤ x≤ 0.22, 0≤ y ≤ 0.24, 2.10 ≤z ≤2.53, and 0.35 ≤ n ≤0.73. The electrochemical characteristics of cobalt-doped todorokites were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries. The first discharge capacity of undoped todorokite electrode was 211 mAh/ g and the discharge capacity became 37 mAh/g after 30 cycles. The Mg0.18Co0.12Mn02.19·0.45 H20 with doping Co 10% displayed the best discharge behavior, which showed a high discharge capacity of 219 mAh/g at first cycle and the cycling capacity of 102 mAh/g after 100 cycles.
出处
《电化学》
CAS
CSCD
北大核心
2010年第1期90-95,共6页
Journal of Electrochemistry
基金
国家自然科学基金(No.20807019)
华中农业大学"国家大学生创新性实验计划"(No.2007006)资助
关键词
常压回流
钙锰矿
钴离子掺杂
锂离子二次电池
正极材料
refluxing at atmospheric pressure
todorokite
cobalt-doped
lithium-ion secondary battery
cathode materials
作者简介
通讯作者，Tel：（86-27）87280271，E-mail：liufan@mail．hzau．edu．cn
