双钙钛矿氧化物La2-xSrxNiMnO6（x=0,0.15）的电磁特性研究  

Electromagnetic properties of double perovskite oxide La2-xSrxNiMnO6 （x=0, 0.15）

作　　者：王骞[1] 王婷[2] 李晓欣 陈金欢 邢茹[2,3] 赵建军[2,3] WANG Qian;WANG Ting;LI Xiaoxin;CHEN Jinhuan;XING Ru;ZHAO Jianjun(Office of Academic, Baotou Teachers College, Inner Mongolia Autonmous Region, Baotou 014030, China;Department of Physical Education and Technology, Baotou Teachers College, Baotou 014030, China;Key Laboratory of Magnetics and Magnetic Materials, Inner Mongolia Autonomous Region,Baotou Teachers College, Baotou 014030, China)

机构地区：[1]包头师范学院教务处,内蒙古包头014030 [2]包头师范学院物理科学与技术学院,内蒙古包头014030 [3]内蒙古自治区磁学与磁性材料重点实验室,包头师范学院,内蒙古包头014030

出　　处：《功能材料》2020年第2期2078-2085,共8页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(11164019,51562032,61565013);内蒙古自治区科学基金资助项目(2015MS0109);内蒙高校科学研究基金资助项目(NJZZ11166,NJZY12202);包头市科学技术局产学研合作资助项目(2014X1014-01,2015Z2011);内蒙古自治区研究生科研创新资助项目(S201710127(S01))

摘　　要：采用固相反应法制备了双钙钛矿锰氧化物La2-xSrxNiMnO6(x=0,0.15)样品。XRD测试结果表明,两个样品成相良好,属于钙钛矿晶体结构;通过磁化强度随温度变化曲线(M-T)可判定Sr掺杂导致样品铁磁性减弱,反铁磁性增强,等温磁化曲线(M-H)可进一步证实这一结论;两个样品的磁滞回线、2K下的磁滞回线的放大图和拉曼光谱测试结果可以共同说明Sr的掺杂使得系统反位无序度和反位缺陷增大、反位无序之间的反铁磁耦合增强、反铁磁性反相边界增加;同时χ^-1-T曲线在居里温度附近向上背离居里-外斯定律情况有减弱的趋势,用反位缺陷与反铁磁耦合强度之间相对强弱关系的变化可以解释这一现象;掺Sr之后,LSNMO系统的FCC和FCW曲线不重合是一级相变的典型特征,用重标定曲线和Arrott曲线可以进一步证实这一现象;同时两样品的电阻率随温度变化结果表明La1.85Sr0.15NiMnO6的金属-绝缘体转变温度降低、在0和2T下测得的电阻率之间的差值增大。A sample of double perovskite manganese oxide La2-xSrxNiMnO6(x=0,0.15)was prepared by solid state reaction.The XRD test results show that the two samples were in good phase and belonged to the perovskite crystal structure.The magnetization with temperature curve(M-T)could be used to determine that the Sr doping led to weakening of the ferromagnetism,antiferromagnetic enhancement,isothermal magnetization curve(M-H).This conclusion could be further confirmed.The hysteresis loop of the two samples,the magnified view of the hysteresis loop at 2 K,and the Raman spectroscopy test results could jointly illustrate the doping of the Sr and the inversion of the system.When the defect increased,the antiferromagnetic coupling between the anti-disorders increased,and the antiferromagnetic inverse boundary increased.At the same time,theχ^-1-T curve had a tendency to diminish from the Curie-Fores law near the Curie temperature.The change of the relative strength between the anti-biting and the antiferromagnetic coupling strength could explain this phenomenon.After Sr doped,the FCC and FCW curves of the LSNMO system did not coincide with each other,which was a typical feature of the first-order phase transition.The curve and the Arrot curve could further confirm this phenomenon.At the same time,the resistivity of the two samples changed with temperature,indicating that the metal-insulator transition temperature of La1.85Sr0.15NiMnO6 decreased at 0 and 2T.Increase in the difference between the resistivity was obtained.

关 键 词：双钙钛矿 反位无序 反相边界 反铁磁耦合 

分 类 号：TM284[一般工业技术—材料科学与工程]