Ca掺杂的GdBaCo2O5+δ的制备和物性研究

摘要

采用固相反应法制备了Gd1-xCax BaCo2O5+δ(x=0、0.1、0.2)层状钙钛矿钴氧化物,通过XRD、SEM、TG和四线法研究了材料的制备和物理性能.结果表明,Ca掺杂的样品主相具有母相GdBaCo2O5+δ的晶体结构,还存在杂相BaCoO2.6；晶胞参数和体积随Ca掺杂量的增加而减小.从室温到1000K,所有样品都经历了金属绝缘体转变和结构相变,Ca掺杂样品的电导率得到大大提高,约为母相的2倍.%Layered perovskite cobalt oxides Gd1-xCaxBaCo2O5+δ(x = 0, 0. 1, 0. 2) were synthesized by solid state reaction. The fabrication and physical properties were investigated by XRD, SEM, TG and four wire method. The experimental results show that Ca doped samples have the main phase of GdBaCo2O5+δ crystal structure and also have the impurity phase BaCoCk 6; the unit cell parmameters and volume of all the samples decrease with Ca doping content increasing. From room temperature to 1000K, all the samples experience metal insulator transition and structure phase transition. The conductivity of Ca doped samples are greatly improved and twice as big as that of the parent phase GdBaCo2O5+δ.