La_(2/3)Ca_(1/3)MnO_3∶Ag_x多晶靶材的制备及其电输运性质  

Preparation and Electrical Transport Property of Polycrystalline La_(2/3)Ca_(1/3)MnO_3∶Ag_x Composites

作　　者：曹明刚[1] 刘翔[1] 张辉[1] 尚杰[1] 段云彪[1] 兰军[1] 张少春[1] 张鹏翔[1,2] 

机构地区：[1]昆明理工大学光电子新材料研究所,云南昆明650051 [2]德国马普固体物理所

出　　处：《材料科学与工程学报》2011年第2期214-216,262,共4页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(50974066);云南省自然科学基金资助项目(2009ZC013M)

摘　　要：采用固相反应法制备了不同Ag掺杂量的La2/3Ca1/3MnO3(LCMO)∶Agx(x为摩尔百分比,x=0.00、0.01、0.05、0.10、0.20、0.30、0.40)多晶靶材,XRD图谱显示所制备样品均为纯相的赝立方钙钛矿结构,并且随着Ag掺杂量的增加,a轴和b轴在0≤x≤0.40范围内有微小的涨落;另外R-T曲线显示,0≤x≤0.05时,金属-绝缘转变温度(Tp)开始升高很快,0.05<x≤0.40时逐渐变缓,最大值为192K,这比化学共沉淀法制备的多晶靶材(273K)低约80K,分析其原因可能是粉体粒度的不同所致。Ag-doped polycrystalline La_2/3Ca_1/3MnO_3（LCMO）∶Ag_x（x = 0.00,0.01,0.05,0.10,0.20,0.30,0.40） targets have been prepared by solid-phase sintering method.X-ray diffraction（XRD） patterns show that the samples have a pseudo-cubic perovskite structure.With the addition of Ag,there is a little change in a-axis and b-axis from x=0.00 to x= 0.40.In addition,R-T curves demonstrate that the metal-insulation transition temperatures（Tp） increases sharply for x0.05,and then increases slowly for x=0.05-0.40.The maximum Tp is 192 K,which is 80 K lower than that made by chemical coprecipitation method.This may be explained by the influence of powder grain size on Tp.

关 键 词：LCMO∶Agx 固相法 多晶靶材 金属-绝缘转变温度 

分 类 号：TM205[一般工业技术—材料科学与工程]