以傳統的球磨法製備出摻雜稀土元素氧化釤的二氧化鈰基固態電解質Ce1-xSmxO2-x/2 (x=0, 0.2, 0.4)粉末，經二階段燒結後，具有高氧離子傳導的能力。
以(X-ray diffraction analysis, XRD)鑑定二氧化鈰之相結構(Fluorite structure)，並利用(Scanning electron microscopy, SEM)觀察比較傳統的一階段燒結與二階段燒結下在不同的燒結溫度下(1500~1600oC)，其微結構之緻密程度與晶粒大小分佈的變化，與(Electron back-scattered diffraction, EBSD)分析其晶界之能量分佈，為了掌握晶界在不同燒結溫度下之變化，利用(Transmission electron microscopy, TEM)觀察傳統的一階段燒與二階段燒結下晶界形貌的變化，最後以交流阻抗量測儀(AC-impedance)量測在不同的環境溫度下(600~800oC)，不同微結構之阻抗性質，並計算不同微結構下晶粒與晶界離子導電性之變化，與活化能的大小。
其中電性表現最好的為二階段燒結的試樣0SDC-1600-1500-20h，在環境溫度800oC下其晶界導電度為1.38×10-3、晶粒導電度為1.41×10-2、整體導電度為1.26×10-2、活化能為0.89 eV。

Samarium doped ceria (SDC) is good candidate for application in intermediate temperature solid oxide fuel cells (IT-SOFC) due to the ability of high oxygen ionic conductivity.
SDC powders Ce1-xSmxO2-x/2 (x=0, 0.2, 0.4) is synthesized by traditional solid state reaction method and sintered to densify in conventional sintering and two-step sintering. The sample were characterized by XRD, SEM, EBSD, TEM and AC-impedance in the temperature range of 500~700oC.
The uniformly particle size (1~4m) of the SDC mixed powders allows the sintering of the samples into highly dense (≅95%) pellet at 1600oC. All powders and pellet were found to be pure CeO2 or ceria-based solutions with fluorite-type structure in X-ray diffractometer. The microstructure of grain size (≅ 8~15m) and grain boundaries in sintered pellets was observed under the SEM and EBSD. The morphology of grain boundaries were defined by high resolution transmission electron microscopy. All the solid oxide electrolytes were characterized by impedance spectroscopy to distinguish the grain and grain boundary electrical properties. The sample 0SDC-1600-1500-20h has the best electrical properties under 800 oC (σgb =1.38×10-3 S/cm, σg =1.41×10-2 S/cm, σeff =1.26×10-2 S/cm, Q =0.89 eV).

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