利用固相反应法合成了层状钙钛矿钴氧化物Yt-xCaxBaCo2O5+δ(x=0,0.1,0.15,0.2)材料,系统研究了材料的氧吸附性能和电输运性质.XRD结果表明Ca2+掺杂的样品具有母相YBaCo2O5+δ层状钙钛矿结构,随着Ca2+掺杂量的增加,样品的晶格参数增大.TG结果显示:从室温到1273 K,所有样品经历了两次吸氧和脱氧的过程,Ca2+掺杂增强了样品的氧脱附性能.在中低温下,约650 K附近.吸氧量达到最大,同时,样品发生了半导体金属转变.Ca2+掺杂量的增加,半导体金属转变温度增大,电导率下降.半导体金属转变与氧变化量δ有关而电导率下降与Ca2+掺杂引起Co3+离子的增加有关.%Layered perovskite cobalt oxide Y1-xCaxBaCo2O5+δ (x=0,0.1, 0.15, 0.2) materials were synthesized by solid state reaction. Oxygen absorption and electrical transport properties of all the samples have been investigated. XRD results indicate that the structure of Ca2+ doped samples has the same Layered perovskite structure of parent phase YBaCo2O5+δ and their lattice constants increase with Ca2+ doping content increase. TG results present that all the samples experience two oxygen absorption and desorption processes from room temperature to 1 273 K and Ca2+ doping can enhance oxygen desorption property. At medium and low temperature (about 650 K), all the samples have the maximal oxygen absorption capability and have the semiconductor-metal transition at the same time. The increase of Ca2+ doping content increases the semiconductor-metal transition temperature and depresses the conductivity. It is argued that the semiconductor-metal transition is related to the oxygen variance S and while the depression of conductivity is related to the increasing of Co3+ induced by Ca2+ doping.
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