【摘要】 采用高压高温方法合成钙钛矿型SmCoO3氧化物,利用XRD,Raman,电导率和热膨胀测试对样品的结构及性能进行表征.实验结果表明,在2.75~4.20 GPa,1 061℃附近,Co2O3和Sm2O3发生固相反应形成SmCoO3,但反应不完全.单相SmCoO3较好的合成条件为3.90 GPa和1 061℃左右.室温Raman谱观察到单相样品中只有SmCoO3正交相的特征峰.SmCoO3样品在327℃以下为绝缘体,在327℃以上电导率随温度升高而增加.热膨胀系数在100~800℃呈线性变化.更多还原

【Abstract】 Perovskite oxide SmCoO3 was prepared by the high pressure and high temperature(HPHT) method.The structure and properties of the samples were investigated by XRD,Raman,electrical conductivity and thermal expansion measurement techniques.The results indicate that the raw materials Co2O3 and Sm2O3 can form SmCoO3 under 2.75~4.20 GPa at about 1 060 ℃,but the reaction was not complete.The single phase SmCoO3 was synthesized under the conditions of about 3.90 GPa and 1 061 ℃.The Raman spectra only shows the characteristic of orthogonal SmCoO3.The single phase SmCoO3 is an insulator under 327 ℃ and its electrical conductivity increases with temperature increasing,which shows an insulator-semiconductor-metal transition.The thermal expansion coefficient of the sample shows a linear change in a temperature range of 100~800 ℃,which is better than that of the sample prepared by solid-state reaction.更多还原