摘要
利用溶胶-凝胶法制备了稀土锰氧化物La0.60Sr0.40-xNaxMn O3(x=0、0.10、0.15、0.20、0.30、0.33、0.35)、La0.60Sr0.40-xKxMn O3(x=0、0.15、0.20、0.30)、Agδ-La0.60Sr0.40-xAgx-δMn O3(x=0、0.15、0.20、0.25、0.30)系列多晶样品。研究发现Na+、K+、Ag+取代部分Sr2+后,当掺杂量x≥0.15时,Na、K、Ag系列样品的晶胞体积均随掺杂量x增加而单调变大,样品居里温度随Na、K、Ag掺杂量x的增加而降低;当Na、K、Ag含量较小时,三个系列样品的电阻率峰值随掺杂量x的增加而减小,当x>0.20时,样品的电阻率峰值随x的增加而增大。对其微观机理进行了讨论,认为相对于替代离子半径,Mn4+与Mn3+离子对数目之比Rn是影响材料以上性质的主要原因。
Perovskite rare-earth manganites polycrystalline samples La0.60Sr0.40-xNaxMnO3 （x=0, 0.10,0.15, 0.20, 0.30, 0.33 and0.35）, La0.60Sr0.40-xKxMnO3 （x=0, 0.15, 0.20 and 0.30） and Agδ-La0.60Sr0.40-xAgx-δMnO3 （x=0, 0.15, 0.20, 0.25 and 0.30） were synthesized by sol-gel method. It is found that when Sr^2＋ions are partly substituted by Na^＋, K^＋or Ag^＋ ions, the crystal cell volume of substituted samples increases monotonically with x for x≥0.15, the Curie temperature of substituted samples decreases with the increasing of x for x≥0.15;the resistivity peak values of substituted samples decreases with the increasing of x for x≤0.20 and increases with x for x〉0.20. And its microscopic mechanism is also discussed, and compared with the ionic radius,the Rn（ ratio of Mn^4＋ and Mn^3＋） is the main factor affecting the material properties.
出处
《磁性材料及器件》
CAS
2015年第3期9-12,共4页
Journal of Magnetic Materials and Devices
基金
国家自然科学基金资助项目(11174069)
河北省自然科学基金资助项目(E2011205083)
河北省基础研究重点资助项目(10965125D)
关键词
锰氧化物
溶胶-凝胶法
掺杂
晶体结构
磁性
电输运性质
manganite
sol-gel method
doping
crystal structure
magnetic properites
electrical transport properties
