聚阴离子掺杂LiMnO_(2-y)X_y(X=BF_4^-,SiO_3^(2-),MoO_4^(2-),PO_4^(3-),BO_3^(3-))材料的合成及其电化学性能  

Synthesis and Electrochemical Properties of Polyanion Doped LiMnO_(2-y)X_y(X=BF_4^-,SiO_3^(2-),MoO_4^(2-),PO_4^(3-),BO_3^(3-)) Materials

作　　者：粟智[1] 叶世海[2] 王永龙[2] 

机构地区：[1]新疆师范大学生命科学与化学学院,乌鲁木齐830054 [2]南开大学化学学院,新能源材料化学研究所,天津300071 Xinjiang Normal Univ, Coll Life & Chem Sci, Urumqi 830054, Peoples R China; Nankai Univ, Inst New Energy Mat Chem, Tianjin 300071, Peoples R China

出　　处：《无机化学学报》2010年第4期693-700,共8页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金课题(No.20773070);新疆师范大学博士科研基金项目(No.XJNUBS0807)资助;新疆高科研计划重点项目(No.XJEDU2009I28)资助

摘　　要：采用水热法合成了聚阴离子掺杂LiMnO2-yXy(X=BF4-,SiO32-,MoO42-,PO43-,BO33-,y=0.01、0.03、0.05)锂离子电池正极材料。通过X射线粉末衍射(XRD)、X光电子能谱(XPS)、扫描电镜(SEM)和恒电流充放实验,研究了不同掺杂离子和掺杂量对产物结构和电化学性能的影响。结果表明,少量聚阴离子的掺杂未改变正交LiMnO2的晶体类型,但增大了材料晶胞体积,改善了材料的电化学循环性能。电化学交流阻抗(EIS)测试结果表明,聚阴离子掺杂增大了材料电荷转移阻抗,但明显提高了材料中Li+的扩散能力。Hydrothermal methods were used to prepare the polyanion-doping LiMnO2-yXy（X=BF4^-,SiO3^2-,MoO4^2-,PO4^3-,BO3^3-） as cathode materials for lithium-ion batteries. The samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectra （XPS）, scanning electron microscope （SEM） and their electrochemical performances were investigated including cycling behavior （CV） and constant current charge-discharge experiment. The results indicate that the low concent ration polyanion dopant does not affect the crystal type of orthorhombic LiMnO2 but considerable improves its electrochemical performances. Electrochemical impedance spectroscopy （EIS） analysis shows that the charge-tranfer resitance and the Warburg impendance decrease obviously as compared to that the undoped LiMnO2 samples, however, The large polyanion doping can enhances fast mobility of Li＋ ions.

关 键 词：聚阴离子 掺杂 锂离子电池 层状LIMNO2 电化学性能 

分 类 号：O614.111[理学—无机化学] TM919.9[理学—化学]