【作者】 宿新泰； 燕青芝； 葛昌纯；

【Author】 SU Xin-Tai, YAN Qing-Zhi, GE Chang-Chun(Laboratory of Special Ceramics and Powder Metallurgy, University of Science and Technology Beijing, Beijing 100083, China)

【机构】 北京科技大学特种陶瓷与粉末冶金研究室实验室；

【摘要】 采用了低温燃烧合成陶瓷粉末的方法——柠檬酸-EDTA法合成了超细中温SOFC电解质La0.9Sr0.1Ga0.8Mg0.2O3-α(LSGM)。TEM和SEM结果表明用该方法合成的物质粒度均匀,颗粒小,在较低温度(1400℃)即可得到高致密样品。通过XRD分析对样品的结构以及生成过程作了研究,结果表明在800℃即初步形成钙钛矿相,在1400℃彻底形成稳定的钙钛矿相,此温度比传统高温固相法要低200℃以上。测定了不同温度下样品的交流谱。结果表明,用柠檬酸-EDTA法低温燃烧合成可减少或者消除晶界电阻,其离子电导率在800℃可达8.2×10-2S/cm。更多还原

【Abstract】 The intermediate-temperature electrolyte with perovskite-type La0.9Sr0.1Ga0.8Mg0.2O3-α(LSGM) was synthesized using citric acid-EDTA combustion method. TEM and SEM indicate that the purity of the product prepared by this method is higher; the grain size is uniformly smaller. They are easily sintered into dense ceramic pellets at 1400℃. The formation process of the LSGM phase was investigated using XRD. The research results show that the LSGM phase was formed essentially at a sintering temperature of 800℃, and the stable perovskite phase was formed completely after a sintering temperature of 1400℃. The sinterability shows that the sintering temperature of the sample, which was synthesized by citric acid-EDTA combustion method, is at least 200℃ lower than that of the conventional solid state method that was reported previously. The electrical properties of the sintered samples were studied by ac impedance technology. Impedance spectra indicate that the grain boundary resistance of the LSGM synthesized by this method is reduced or eliminated. The conductivity of a sample is 8.2×10-2S/cmat800℃.更多还原