利用溶胶-凝胶法制备了稀土锰氧化物La0.60Sr0.40-xNaxMnO3(x=0、0.10、0.15、0.20、0.30、0.33、0.35)、La0.60Sr0.40-xKxMnO3(x=0、0.15、0.20、0.30)、Agδ-La0.60Sr0.40-xAgx-δMnO3(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 Sr2+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 Mn4+and Mn3+) is the main factor affecting the material properties.
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