CAJ | 학술논문

我们用传统的固相反应法制备了(La0.7Ca0.3MnO3)1-x(MgAl2O4)x复合样品.通过XRD分析发现在此系列复合样品中La0.7Ca0.3MnO3和MgAl2O4两相共存;电阻率温度关系分析表明MgAl2O4的引入没有改变母体相在温度TP1处本征的金属-绝缘体转变峰,但使复合样品在较低温度TP2处出现另外一个电阻率峰值.有趣的是,随着MgAl2O4掺量的增加,在低掺量时,TP2向低温偏移很快;但在高掺量时,TP2向低温偏移较慢.
아문용전통적고상반응법제비료(La0.7Ca0.3MnO3)1-x(MgAl2O4)x복합양품.통과XRD분석발현재차계렬복합양품중La0.7Ca0.3MnO3화MgAl2O4량상공존;전조솔온도관계분석표명MgAl2O4적인입몰유개변모체상재온도TP1처본정적금속-절연체전변봉,단사복합양품재교저온도TP2처출현령외일개전조솔봉치.유취적시,수착MgAl2O4참량적증가,재저참량시,TP2향저온편이흔쾌;단재고참량시,TP2향저온편이교만.
The composites of(La0.7Ca0.3MnO3)1- x(MgAl2O4)x(x represents the volume fraction)were synthesized by conventional solid-state reaction method.The results of X-ray diffraction(XRD)indicates that the MgAl2O4 and La0.7Ca0.3 MnO 3 phase are coexist in the composites.The detailed electrical characterizations for all the samples show that MgAl2O4 almost does not change intrinsic insulator/metal(I/M)transition temperature(TP1),but causes a new resistivity peak at a much lower temperature(TP2).It is very interesting that at low doping level,MgAl2O4 plays an important role in the grain boundary region and causes the rapid decrease of TP2 with increasing x.But at high doping level,TP2 decreases slowly.