摘要
以MnSO_(4)为基础锰源,分别采用3种路径(MnSO_(4)+KMnO_(4)+LiOH一步水热法;自制MnOOH/Mn_(3)O_(4)+LiOH分步水热法)制备出o-LiMnO_(2),然后在400℃下焙烧6 h获得富锂锰氧化物Li_(1.6)Mn_(1.6)O_(4).讨论了锂锰比(Li和Mn的摩尔比,下同)工艺参数对合成o-LiMnO_(2)过程的影响,并使用X射线衍射仪和扫描电镜对3种路径制备的产物进行比较分析.结果表明:自制Mn_(3)O_(4)的分步法在锂锰比为6~12时可制得纯相o-LiMnO_(2),一步法与自制MnOOH锰源的分步法在锂锰比4~20时,制备的LiMnO_(2)均混有杂质相;3种路径制得的o-LiMnO_(2)经焙烧后,均可得到结晶度较好的纳米级Li_(1.6)Mn_(1.6)O_(4)锂离子筛前驱体,由Mn_(3)O_(4)制备的o-LiMnO_(2)呈现特殊棒状形貌,而由MnOOH制备的o-LiMnO_(2)则呈立方状形貌.
MnSO_(4) was used as the basic manganese source to prepare o-LiMnO_(2) by three routes(MnSO_(4)+KMnO_(4)+LiOH one-step hydrothermal method;homemade MnOOH/Mn_(3)O_(4)+LiOH stepwise hydrothermal method),and then the lithium-rich manganese oxide Li_(1.6)Mn_(1.6)O_(4) was obtained by roasting at 400℃ for 6 h.The effects of the process parameters of lithium-manganese ratio(molar ratio of Li and Mn,the same below)on the process of synthesizing o-LiMnO_(2) were discussed,and the products prepared by three routes were comparatively analyzed by X-ray diffractometer and scanning electron microscopy.The results show that:the stepwise method with homemade Mn_(3)O_(4) can produce pure phase o-LiMnO_(2) at Li-Mn ratios of 6~12,and the one-step method and the stepwise method with homemade MnOOH manganese source,at Li-Mn ratios of 4~20,the resulting LiMnO_(2) are mixed with impurity phases;roasting the three kinds of o-LiMnO_(2),all of them can produce nano-sized Li_(1.6)Mn_(1.6)O_(4) lithium-ion sieve precursors with better crystallization degree.The morphologies of the products are different in different directions;the o-LiMnO_(2) prepared from Mn_(3)O_(4) shows a special rod-like morphology,while the o-LiMnO_(2) prepared from MnOOH shows a cubic morphology.
作者
刘肖
李凤华
李英楠
樊瑞
陈晓志
Liu Xiao;Li Fenghua;Li Yingnan;Fan Rui;Chen Xiaozhi(School of Metallurgy,Northeastern University,Shenyang 110819,China)
出处
《材料与冶金学报》
CAS
北大核心
2023年第6期547-552,共6页
Journal of Materials and Metallurgy
基金
国家自然科学基金面上项目(U1261120)。
