合成及电性能
(江苏科技大学 数理学院，镇江 212003)
摘 要: 采用固相反应法合成一系列样品Sm0.9Ca0.1Al1−xZnxO3−δ(x=0，0.03，0.05)。利用X射线衍射和扫描电镜研究样品的结构、微观形貌和烧结性能，用交流阻抗谱测量Sm0.9Ca0.1Al0.97Zn0.03O3−δ在500~1 000 ℃的电导性能。结果表明：在1 650 ℃烧结24 h可以获得单相样品，Zn2+在B位的固溶度为3%~5%，样品的相对密度为92.3%。Ca、Zn双掺杂能大大提高样品的电导性能，800 ℃时总电导率为0.39 S/m，ln(sT)与1/T关系曲线呈一折线，高温电导活化能小于低温电导活化能，710 ℃以上的电导活化能为0.66 eV，710 ℃以下的电导活化能为1.18 eV。
关键字: 氧离子导电性；双掺杂铝酸钐；交流阻抗谱；电导率
SmAlO3-based oxygen ionic conductor
（School of Mathematics and Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China）
Abstract: A series of samples Sm0.9Ca0.1Al1-xZnxO3-δ(x=0, 0.03, 0.05) were synthesized by solid state reaction method. The microstructure, morphology and sinterability of the samples were characterized by X-ray diffraction and scanning electron microscope. And the alternating current impedance measurements were performed at 500−1 000 ℃. The results show that the single phase samples can be obtained when the samples are sintered at 1 650 ℃ for 24 h, and the solid solubility of Zn2+ on B site should be in the range of 3%−5%, and the relative density of Sm0.9Ca0.1Al0.97Zn0.03O3−δ is 92.3%. The doubly doping of Ca and Zn can improve consumedly the electrical properties of SmAlO3, and the total conductivity of Sm0.9Ca0.1Al0.97Zn0.03O3−δ is 0.39 S/m at 800 ℃. The curves of ln(σT) against 1/T reveal two straight lines intersecting at 710 ℃. The activation energy of oxygen-vacancy motion above 710 ℃ is lower than that below 710 ℃.
Key words: oxygen ionic conduction; doubly doped SmAlO3; alternating current impendence spectrum; conductivity
