以反應燒結法製備固態氧化物燃料電池

Preparation of solid oxide fuel cells by a reaction-sintering process

黃昱霖(Yuh-Lin Huang)

指導教授 ： 劉依政

崑山科技大學/工程學院/電子工程研究所/碩士(2010年)

摘要

本論文研究反應燒結法製備固態氧化物燃料電池(SOFC)之可行性。在反應燒結製程中，原料不經任何煆燒步驟直接成型燒結。GdxCe(1-x)O(2-x/2)(x=0.1,0.2) 電解質陶瓷在1500oC燒結6小時可得到晶粒尺寸大小4-5μm，且顯示出有些許孔洞存在。需在1500oC以上燒結才能緻密化。
La0.8Sr0.2FeO3陰極陶瓷在1200oC至1270oC燒結2小時可以獲得23.9%-38.2%之孔隙率。在1200oC至1270oC燒結6小時可獲得2.3%-32.6%孔隙率。經2小時燒結之La0.8Sr0.2FeO3陶瓷有細小晶粒，尺寸大小約1μm。La0.8Sr0.2FeO3陶瓷燒結6小時可觀察到孔隙率有明顯的減少，但晶粒尺寸大小無明顯變化。
La0.85Sr0.15MnO3陰極陶瓷燒結在1170oC至1270oC可獲得15%-38%孔隙率。多孔結構之La0.85Sr0.15MnO3陶瓷在1200oC燒結2小時可得到之晶粒尺寸大小3μm。隨著提高燒結溫度及時間，孔隙率下降而密度提升。因此可藉燒結溫度與時間控制孔隙率。
Sr0.895Y0.07TiO3陽極陶瓷在1250oC燒結4小時可獲得晶粒尺寸大小1μm。且從掃描式電子顯微鏡觀察亦有多孔性結構。熱膨脹率以近乎線性關係隨測試溫度增加而增加，La0.8Sr0.2FeO3與La0.85Sr0.15MnO3之熱膨脹率在9.74×10-6-9.85×10-6，皆與Gd0.9Ce0.1O1.95和Gd0.2Ce0.8O1.95之熱膨脹率1.09×10-5-1.08×10-5相近。

關鍵字

固態氧化物燃料電池 反應燒結法

並列摘要

Solid oxide fuel cells (SOFCs) prepared by the reaction-sintering process were investigated in this thesis. The mixture of raw materials was sintered directly without any calcination step. Grains of 4-5 μm were observed in porous GdxCe(1-x)O(2-x/2) (x=0.1, 0.2) electrolyte ceramics sintered at 1500oC for 6 h. Temperatures higher than 1500oC were necessary for highly dense GdxCe(1-x)O(2-x/2) pellets.
La0.8Sr0.2FeO3 cathode ceramics with 23.9-38.2% porosity could be obtained after 2 h sintering at 1200-1270oC. 2.3-32.6% porosity formed in 6 h sintering La0.8Sr0.2FeO3 pellets. Grains about 1μm formed in 2-6 h sintering La0.8Sr0.2FeO3. 15-38% porosity was measured in La0.85Sr0.15MnO3 cathode ceramics sintered at 1170-1270oC. Porous pellets with ~3μm grains were found in La0.85Sr0.15MnO3 sintered at 1200oC for 2 h. The amount of pores deceased with increased sintering temperature and soak time. The porosity could be effectively controlled by adjusting the sintering temperature and soak time. Grains of ~1 μm were observed in porous Sr0.895Y0.07TiO3 anode ceramics sintered at 1250oC for 4 h.
Thermal expansion coefficient of La0.8Sr0.2FeO3 and La0.85Sr0.15MnO3 was found in the range 9.74×10-6-9.85×10-6 which is compatible with 1.09×10-5-1.08×10-5 for Gd0.9Ce0.1O1. 95 and Gd0.2Ce0.8O1.9.

並列關鍵字

Solid Oxide Fuel Cell Reaction-Sintering Process

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