کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1465293 | 989688 | 2009 | 9 صفحه PDF | دانلود رایگان |
Fine Ce0.8Sm0.2O1.9 (SDC) powders with a fluorite cubic phase were prepared using a urea-combustion technique. The sinterability and microstructural evolution of the resulting ceramics were investigated. The results indicate that the ceramics sintered above 1350 °C display relative densities of about 98.5% along with significant grain growth. With respect to their electrical conduction properties, the specimens sintered above 1350 °C exhibit an excellent total ionic conductivity of 0.082 S cm−1 at 800 °C in air. However, when measured in an N2 + 33.3%H2 atmosphere, a pronounced Warburg feature appears in the impedance plots of the SDC ceramics, together with a significant increase of the total conductivity at measuring temperatures above 550 °C, due to the introduction of a mixed Ce4+/Ce3+ valence state and the generation of the electronic conduction in the reducing atmosphere.
Journal: Ceramics International - Volume 35, Issue 4, May 2009, Pages 1335–1343