為了改善BaCe0.8-xZrxDy0.2O3-δ材料系統的熱穩定性，本研究以化學法合成SrCe0.8-xZrxDy0.2O3-δ (x=0.1-0.4) 和BaCe0.5M0.3Dy0.2O3-δ (M = Ti, Sn, Hf, Zr)，分析其成分對導電率與熱穩定性的影響。實驗結果發現導電度與晶格常數和結構對稱性成正相關；熱穩定性則隨著結構對稱性和摻雜離子的電負度 (Electronegativity) 增加而提高，且不同成分的相對穩定性與熱力學估算的趨勢接近。BaCe0.5Sn0.3Dy0.2O3-δ在本實驗的所有成分中對二氧化碳和水具有最佳的熱穩定性，兼具不錯的導電度。進一步探討其缺陷化學，發現導電度與氧分壓的1/4次方有線性關係，與實驗結果相符。由離子與電洞遷移數得知，BaCe0.5Sn0.3Dy0.2O3-δ在低氧分壓下為純離子導體，在高氧分壓下則為離子與電洞的混合導體，有潛力做為IT-SOFC的陽極、電解質和陰極材料。

目錄……………………………………………………………………I
圖目錄…………………………………………………………………III
表目錄…………………………………………………………………VII
1. 前言…………………………………………………………………1
2. 實驗方法……………………………………………………………5
2.1 起始原料…………………………………………………………5
2.2 粉體合成…………………………………………………………5
2.2.1 合成SrCe0.8-xZrxDy0.2O3-δ (x=0.1-0.4) 粉末………………5
2.2.2 合成BaCe0.5M0.3Dy0.2O3-δ , M = Ti, Zr, Sn, Ce, Hf 粉末…6
2.3 試片製作…………………………………………………………7
2.4 基本性質測試……………………………………………………8
2.4.1 熱重熱差分析………………………………………………8
2.4.2 X-ray繞射分析……………………………………………8
2.4.3 顯微結構觀察………………………………………………8
2.5 導電率量測………………………………………………………8
2.6 熱穩定性測試……………………………………………………9
2.6.1 對二氧化碳之穩定性………………………………………9
2.6.2 對水之穩定性……………………………………………10
3. 結果與討論…………………………………………………………11
3.1 SrCe0.8-xZrxDy0.2O3-δ與BaCe0.8-xZrxDy0.2O3-δ (x=0.1-0.4)……11
3.1.1 導電率………………………………………………………11
3.1.2 對二氧化碳之熱穩定性……………………………………13
3.2 BaCe0.5M0.3Dy0.2O3-δ , M = Ti, Zr, Sn, Ce, Hf…………………15
3.2.1 導電率………………………………………………………16
3.2.2 對二氧化碳之熱穩定性……………………………………17
3.2.3 對水之熱穩定性……………………………………………19
3.2.4 BaCe0.5Sn0.3Dy0.2O3-δ之導電機制…………………………21
4. 結論………………………………………………………………24
5. 參考文獻……………………………………………………………26

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