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分别采用固相法和共沉淀法工艺制备了不同Ag掺杂量的La2/3Sr1/3MnO3∶Agx(LSMO∶Agx,x为摩尔百分比,x=0.00、0.10、0.20、0.30、0.40)多晶材料,通过XRD和R-T对La2/3Sr1/3MnO3∶Agx材料的结构和性能进行测试分析。XRD分析结果表明,系列样品为正交菱面体结构,没有出现Ag元素的峰,这与Ag在高温烧结时的挥发有关;随着组分x的增加,固相法系列样品晶胞体积呈无规律膨胀,而共沉淀系列样品晶胞体积呈增大趋势,这可能是由于固相法系列样品的粒径较大且不均匀,导致LSMO∶Agx晶格有较多的缺陷使晶胞体积发生膨胀,而共沉淀系列样品的粒径较小且均匀,Ag+进入晶格替代Ag位的La3+或Sr2+,引起晶胞体积发生微小膨胀。R-T分析结果表明,相对于同一组分x,共沉淀比固相法系列样品有更低的电阻率及更高的TCR值,Ag掺杂能有效改善LSMO材料的电阻率及TCR;共沉淀系列样品Ag掺杂对LSMO材料电阻率及TCR调制作用更明显。
La2 / 3Sr1 / 3MnO3: Agx (LSMO: Agx, x is mole percent, x = 0.00,0.10,0.20,0.30,0.40) polycrystalline materials with different amounts of Ag doping were prepared by solid state and coprecipitation methods respectively , The structure and properties of La2 / 3Sr1 / 3MnO3: Agx materials were tested by XRD and RT. The results of XRD analysis showed that the series of samples were orthorhombic rhombohedral with no peak of Ag, which was related to the volatilization of Ag at high temperature. With the increase of component x, the unit cell volume of solid sample was The law of expansion, and coprecipitation series of samples unit cell volume increases, which may be due to solid-phase sample series of large and uneven particle size, resulting in LSMO: Agx lattice lattice defects have more defects so that unit cell volume Swollen, while the coprecipitated sample size smaller and uniform, Ag + into the lattice to replace the Ag bit of La3 + or Sr2 +, causing a slight expansion of the unit cell volume. The results of RT analysis show that the coprecipitation has lower resistivity and higher TCR value than the solid phase sample, and the Ag doping can effectively improve the resistivity and TCR of the LSMO material. The effect of Ag doping on the resistivity and TCR modulation of LSMO material is more obvious.