Pr_(0.75)Na_(0.25)Mn_(1-x)Fe_xO_3的制备及磁学和输运性质研究  

SYNTHESIS,MAGNETIC AND TRANSPORT PROPERTIES OF Pr_(0.75)Na_(0.25)Mn_(1-x)Fe_xO_3(0.0≤x≤0.3)

作　　者：李玉[1] 于海鹏[2] 戚大伟[1] 程倩[2] 王在山[1] 

机构地区：[1]东北林业大学理学院物理系,哈尔滨150040 [2]东北林业大学材料科学与工程学院,哈尔滨150040

出　　处：《低温物理学报》2010年第1期27-32,共6页Low Temperature Physical Letters

基　　金：哈尔滨市科技创新人才专项基金(项目编号:2009RFQXG049);黑龙江省教育厅科学技术研究基金(项目编号:11523010);哈尔滨市科技攻关计划(项目编号:2007AA1CG062)资助的课题~~

摘　　要：采用溶胶凝胶法通过较低温度、较短的烧结时间制备了单相的多晶钙钛矿Pr0.75Na0.25Mn1-xFexO3(0≤x≤0.3),避免了Na元素的挥发及锰氧化物的析出,使Pr1-xNaxMnO3中Na的最大掺入量由文献报道的0.19提高到0.25,样品单相性得到大幅度提高.系列样品的磁化强度、电阻率随温度的变化关系表明2%的Fe掺杂便能大大减弱低温电荷有序;在x≤0.05时系列样品磁化强度随Fe含量的增加而增加,电阻率随Fe含量的增加而下降,然后二者随Fe含量进一步增加均朝相反的趋势变化.用几何效应(Fe3+的几何尺寸大小)和电子结构的影响两个方面的竞争解释这种现象.The single-phase polycrystalline perovskites Pr0.75Na0.25Mn1-xFexO3（0.0≤x≤0.3） were prepared for the first time by a sol-gel technique, which offers shorter sintering time and lower temperature to avoid the volatilization of Na and the precipitation of manganese oxide. As a result, the maximum sodium solubility in Pr1-x NaxMnO3 was improved from 0. 19 as the literature report to 0. 25, and the degree of single-phase was significantly improved. The temperature dependence of magnetization and resistivity of the samples series exhibits that long-range CO is disrupted even for 2% Fe doping level The magnetization increases and resistivity decreases with increasing Fe doping for x≤0. 05, and then both of them vary to opposite tendency with further increasing Fe doping. The effects of Fe doping on Pr0.75Na0.25Mn1-xFexO3 compounds can be analyzed from the competition of two different aspects, namely the geometric effect （size of the dopant） and electronic configurations.

关 键 词：磁化强度 电阻率 锰氧化物 溶胶凝胶法 

分 类 号：O482.5[理学—固体物理]