固相法制备La_(2/3)Sr_(1/3)MnO_3:Ag_x多晶材料及其性能研究  

Properties of LSMO:Ag_x Polycrystalline Material Prepared by Solid State Reaction

作　　者：凌一峰[1] 刘翔[1] 陈清明[1] 晏益志[1] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093

出　　处：《热加工工艺》2013年第16期25-27,共3页Hot Working Technology

基　　金：国家自然科学基金资助项目(0974066);云南省自然科学基金资助项目(2009ZC013M);昆明理工大学分析测试基金项目(2010001和2011040)

摘　　要：采用固相法合成制备La2/3Sr1/3MnO3：Agx（LSMO：Agx,其中x为Ag掺杂量的摩尔比,x=0.00、0.10、0.20、0.30、0.40）多晶材料。通过X射线衍射和R-T对LSMO：Agx材料的结构和性能进行测试分析。结果表明：La2/3Sr1/3MnO3：Agx（x=0.00,0.10,0.20,0.30,0.40）多晶样品,x=0.00样品研磨后的粉体粒度D50=6.66μm,所有样品都具有正交菱面体结构,没有出现Ag元素的衍射峰,这与Ag在高温烧结时的挥发有关;随着Ag掺杂量从x=0.00增加到x=0.40,样品的晶胞体积在348.6～350.6,说明Ag并没有有效替位掺杂,主要以晶界析出为主;随着Ag掺杂量的增加,电阻率归一化值随之下降,样品电阻率降低;LSMO：Agx多晶材料Tp值在253～298K,且随组分增加呈上升趋势。La2/3Sr1/3MnO3：Agx （LSMO：Agx, x is molar percentage, x=0.0,0.10,0.20,0.30,0.40 ） polycrystaUine materials were prepared by solid state reaction methods. The microstructure and performance of the materials were investigated by XRD and R-T. The results show that the dimension （D） of the sample powder is 6.66 I-~m after grinding, which is prepared by the ratio of LazoSr1/3MnO3：Ag, （x=0.00）. AI samples have the structure of orthorhombic rhombohedral crystal structures and diffraction peaks of Ag have not appeared, which is related to the volatilization of Ag in the high-temperature sintering. The crystal volume changes in the range of 348.6A and 350.6A, because of the adjunction of Ag changing from x=0.00 to x=0.40, That indicates that the adjunction of Ag is not effective for the displacement and probably performs as grain boundary precipitation. The R-T results show that with the increase of x component, the resistivity normalized values decrease, either does the resistivity. Te values of LSMO：Ag, composite increases from 253 K to 298 K with the increase of Ag content.

关 键 词：LSMO多晶材料 AG掺杂 固相法 

分 类 号：TG113.2[金属学及工艺—物理冶金]