臺灣博碩士論文加值系統

本實驗中以溶膠凝膠合成法來製備多孔、純質之錳酸鍶鑭(LSM)陰極材料，經由薄膜製程，製備出高導電性之層狀電極，以應用於固態氧化物燃料電池之陰極。實驗中材料之製備以聚丙烯酸(PAA)為高分子添加劑，經由適當之乾燥過程及熱處理，利用X光繞射進行LSM粉末及薄膜之相鑑定。微結構方面利用光學顯微鏡、掃瞄及穿透式電子顯微鏡進行觀察和量測。以四點式直流電電阻法來進行不同形態LSM薄膜之電性量測。實驗結果顯示，LSM粉末製程中，利用(P)AA/LSM=2之比例，可在500℃溫度下生成純LSM結晶相。以旋鍍法而言，LSM濃度、高分子比例及前驅溶液之黏度值，均控制薄膜變化，薄膜形態亦隨之有所差異。實驗結果顯示，在固定3000rpm、30秒條件，1M LSM濃度、(P)AA/LSM比例=2為最佳之製程條件，此條件下所製備出之多層薄膜電極具有微細均質孔隙，在1000℃溫度下之導電度為6.5 S/cm，活化能為18.6 kJ/mole。

In this research, the LSM precursors were synthesized by sol-gel method using polyacrylic acid (PAA) as the chelating, and then spin-coats on 8Y-ZrO2 substrate to prepare pure and porous layer for cathode application in solid oxide fuel cell (SOFC). The LSM powders and film after dried and sintered at suitable temperatures were characterized by X-ray diffractometry (XRD), optical, scanning, and transmission electron microscopes (OM, SEM and TEM). The conductivity of LSM films was measured by four-probe DC measurement. The results show that the concentration of LSM solution, the molar ratio of (P)AA/LSM, and the viscosity of precursors are the important factors to prepare porous and uniform LSM films. The optimal processing conditions for the spin-coating are using 1.0 M LSM precursor with (P)AA/LSM=2, spinning at 3000 rpm for 30 s. The made films in homogenous microstructure and micro-crack-free states can be obtained after sintering at 1000℃ for 2h.. The best conductivity of multi-layer LSM film with (P)AA/LSM=2 sintered at 1000℃ equals to 6.5 S/cm with the temperature dependence (1/T) by an activation energy of 18.6 kJ/mole.

一 序論………………………………………….………………………1
1-1 前言………………………………………………………………1
1-2 研究目的…………………………………………………………2
二 文獻回顧…………………………………………………………….3
2-1 錳酸鑭(LM)的應用………………………………………………3
2-1-1 LSM電極材料的應用…………………………………………3
2-2 錳酸(鍶)鑭之合成………………………………………………7
2-2-1 固相法[7、8]……………………………………………………7
2-2-2 液相法[9、10]………………………………………………….8
2-2-3 氣相法 ……………………………………………………10
2-3 LSM薄膜的製備…………………………………………………11
2-4、LSM電性探討[29、30]………………………………………………17
2-4-1、添加Sr對LSM電性的影響[32~33]…………………………20
2-4-2、溫度對LSM電性的影響[27] ………………………………21
2-4-3、電極型態對導電性的影響 ………………………………21
三、實驗流程………………………………………………………….23
3-1、實驗設計………………………………………………………23
3-2、實驗材料………………………………………………………26
3-3、氧化鋯基材的製備……………………………………………26
3-4、LSM粉末之製備…………………………………………………27
3-4-1、LSM粉末製備…………………………………………….27
3-4-2、乾壓成型…………………………………………………29
3-4-3、粉末燒結…………………………………………………29
3-5、LSM薄膜之製備………………………………………………29
3-5-1、旋轉塗怖 …………………………………………………29
3-5-2、乾燥及煆燒………………………………………………29
3-6、性質分析………………………………………………………30
3-6-1、燒結體密度量測…………………………………………30
3-6-2、熱分析……………………………………………………30
3-6-3、晶粒尺寸量測 ……………………………………………31
3-6-4、微結構觀察 ………………………………………………31
3-6-4-1、掃瞄式電子顯微鏡（SEM）試片製作及觀察………31
3-6-4-2、穿透式電子顯微鏡（TEM）試片之製作及觀察……32
3-6-5、比表面積與孔洞尺寸量測………………………………33
3-6-6、黏度量測…………………………………………………33
3-6-7、電性量測…………………………………………………33
四、結果與討論 ………………………………………………………35
4-1、LSM粉末的合成…………………………………………………35
4-1-1、熱分析 ……………………………………………………35
4-1-2、添加(P)AA對LSM相生成之影響 ………………………38
4-1-3、PAA對LSM粉末晶徑的影響………………………………51
4-2、薄膜製備及型態分析…………………………………………60
4-2-1、不同比例PAA/LSM對黏度的影響………………………60
4-2-2、添加不同比例(P)AA/LSM對薄膜型態的影響 …………64
4-2-3、不同LSM濃度對於LSM薄膜的影響 ……………………75
4-3、LSM電性量測 ………………………………………………… 94
五、結論 ……………………………………………………………112
附錄一、奈米粉末之燒結收縮測試…………………………………115
A-1、研究目的 ……………………………………………………115
A-2、實驗結果與討論………………………………………………116
A-3 結論……………………………………………………………118
六、參考文獻………………………………………………………125

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