脉冲激光沉积MnF2薄膜的电化学性能  

Electrochemical Properties of MnF_2 Films Fabricated by Pulsed Laser Deposition

作　　者：崔艳华[1,2] 薛明喆[3] 胡可[3] 李达[3] 汪小琳[1] 苏伟[2] 刘效疆[2] 孟凡明[2] 傅正文[3] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,绵阳621900 [2]中国工程物理研究院电子工程研究所,绵阳621900 [3]复旦大学化学系,激光化学研究所,材料科学系,上海市分子催化和功能材料重点实验室,上海200433

出　　处：《无机材料学报》2010年第2期145-150,共6页Journal of Inorganic Materials

基　　金：中国工程物理研究院科学技术基金(2007A0502)

摘　　要：采用脉冲激光沉积法在不锈钢基片上制备了纳米结构的MnF2薄膜.充放电测试显示该薄膜在2μA/cm2的放电电流下,前50次循环具有350~530mAh/g的可逆容量.在循环伏安测试中得到了0.5和1.0V的可逆氧化还原峰,分别代表了MnF2在充放电时的可逆反应.薄膜的晶体结构和形貌采用X射线衍射仪（XRD）和扫描电子显微镜（SEM）分析,充放电后薄膜的组成与结构通过高分辨电子显微镜和选区电子衍射来表征.实验结果揭示了纳米结构MnF2薄膜与Li的电化学反应机理,LiF在首次放电后形成的纳米粒子在过渡金属Mn颗粒的驱动下,可以发生可逆的分解和形成.MnF2薄膜较小的极化和较高的容量使其可用作锂离子电池阳极材料.Nanostructured MnF2 thin films were fabricated by using pulsed laser deposition on stainless steel substrate at room temperature.The reversible discharge capacities of MnF2 thin film electrode in the ranges from 350mAh/g to 530mAh/g was achieved during the first 50 cycles at the current of 2μA/cm2 from cyclic voltammograms curves of Li/MnF2 cell.Reduction and oxidation peaks at 0.5V and 1.0V were detected which indicated the reversible formation and decomposition of reaction of MnF2.The structure and morphology of the as-deposited films were characterized by X-ray diffraction and scan electronic microscopy.The electrochemical reaction of MnF2 thin film electrode was investigated by the high-resolution transmission electron microscope and selected-area electron diffraction measurements.The results demonstrated that nanosized manganese particles formed in initial discharge process could reversible drive the decomposition and formation of LiF.The low polarization and high capacity of MnF2 thin film show that it is a promising lithium-storage materials for future rechargeable lithium batteries.

关 键 词：MnF2 薄膜 脉冲激光沉积 锂离子电池 

分 类 号：O646[理学—物理化学]