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Title

高溫固態電解質型燃料電池之研究與發展

Research and Development of High-Temperature Solid-State Electrolyte Ceramic Fuel Cell

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[[abstract]]氧化鉍因具有高溫氧離子導電性質而引起廣泛的討論。為求能將氧化鉍高溫氧離子導電性質之使用範圍予以擴大,經由先前研究學者發現加入稀土元素或過渡元素可以使氧化鉍之高溫相穩定化至較低溫度。所以本實驗是以加入稀土元素和過渡元素經由高溫熱壓方法縮短燒結所須時間。由X-光繞射儀 ( XRD ) 判斷各成份對氧化鉍高溫相之穩定化能力並與熱差分析儀 ( DTA ) 前後相互印證,再輔以掃瞄式電子顯微鏡 ( SEM ) 觀察其燒結之微結構組織,由熱膨脹儀 ( Dilatometry ) 量測各成份試片對溫度變化之熱膨脹係數,做為電極接觸面之熱膨脹性質之探討,以LCR meter量測各試片之導電率與溫度的關係用以判別各試片之電性優良與否。 在本實驗中高溫熱壓被証實可有效大幅的縮短燒結所需時間,來使加入的稀土元素和過渡元素完全作用而形成固溶體。由XRD的觀察發現不同成份添加量對相的穩定性有影響,以Y2O3及Nb2O5穩定高溫相之穩定性最佳。同時SEM的觀察顯示出微觀組織的變化和相組成有關,在monoclinic phase為板狀結構,cubic phase時為等軸晶結構,rhombohedral phase則是twin結構。DTA曲線被用來間接說明空冷的室溫相和高溫相一次相變化的關係。在不同氧化物系統中,以Y2O3 25 mol% 及Nb2O5 12 mol% 在700℃時具最佳之導電率,導電率分別為0.049 S㎝-1及0.047 S㎝-1。

[[abstract]]Bismuth-oxide-containing materials have been extensively studied because of their excellent ionic conductivity at high temperatures. For obtaining a wide temperature and composition range forδ- Bi2O3 , several oxides such as rare earth oxides and transition metal oxides are used to stabilize this phase at low temperatures. In this study, a hot-pressing technique is used to fabricate these materials at different temperatures. Several analytical methods such as XRD, DTA, SEM, Dilatometric, and LCR meter method are also used to determine the relationships among dopant’s composition, phase, microstructure, and ionic conductivity. The hot-pressing method is found to be a powerful fabrication method for fully densifying bismuth-oxide-containing materials at 700℃~830℃in a short period of time 30 min . The stabilization effect ofδ- Bi2O3 is closely related to dopant’s composition. Among these oxide dopants, Y2O3 and Nb2O5 have better stabilization effects for high-temperature cubic phases. Fractographs of sintered specimens change with the phase and phase content. With the monoclinic, cubic phase, or rhombohedral phase, the corresponding fractograph is layered, intergranular, or twin-related morphology respectivity. Furthermore, the correlations between the high-temperature phase and the phase in the quenched specimen are explained from DTA curves. In these Bi2O3-MxOy binary systems, dopants Y2O3 and Nb2O5 show excellent ionic conductivities at 700℃, which are 0.049 S㎝-1 for 25 mol% Y2O3 and 0.047 S㎝-1 for 12 mol% Nb2O5.

[[note]][1] K. Kordesch, and G. Simader, “Fuel Cells and Their Applications,” VCH Publishers, Inc., New York, NY (USA) (1996). [2] 吉澤四郎編, 賴耿陽譯, “燃料電池與電貯存系統,” 復漢出版社印行 (1994). [3] 吉澤四郎監修, 賴耿陽譯, “最新電池工學,” 復漢出版社印行 (1990). [4] C.N.R. Rao, G.V.Subba Rao, and S. Ramdas, ”Phase Transformations and Electrical Properties of Bismuth Sesquioxide,” Journal of Physical Chemistry, 73, 672-5 (1969). [5] A. V. Joshi, S. Kulkarni, J. Nachlas, J. Diamond, and N. Weber, “Phase Stability and Oxygen Transport Characteristics of Yttria- and Niobia- Stabilized Bismuth Oxide,” J. Material. Sci., 25, 1237-45 (1990). [6] K. Z. Fung and A. V. Virkar, “Phase Stability, Phase Transformation Kinetics, and Conductivity of Y2O3-Bi2O3 Solid Electrolytes Containing Aliovalent Dopants,” J. Am. Ceram. Soc, 74[8] 1970-80 (1991). [7] R. K. Datta and J. P. Meehan, “The System Bi2O3-R2O3 (R=Y,Gd),” Z. Anorg. Allg. Chem., 383, 328-37 (1971). [8] T. Takahashi, T. Esaka, and H. Iwahara, “High Oxide Ion Conduction in the Sintered Oxides of the System Bi2O3-Gd2O3,” J. App. Electrochem., 5, 197-202 (1975). [9] T. Takahashi, H. Iwahara, and T. Arao, “High Oxide Ion Conduction in Sintered Oxides of the System Bi2O3-Y2O3,” J. App. Electrochem., 5, 187-95 (1975). [10] D. Liu, Y. Liu, S. Q. Huang, and X. Yao, “Phase Structure and Dielectric Properties of Bi2O3-ZnO-Nb2O5-Based Dielectric Ceramics,” J. Am. Ceram. Soc. 76 [8] 2129-32 (1995). [11] K. Z. Fung, J. Chen, and A. V. Virkar, “Effect of Aliovalent Dopants on the Kinetics of Phase Transformation and Ordering in RE2O3-Bi2O3 (RE=Yb, Er, Y, or Dy) Solid Solutions,” J. Am. Ceram. Soc. 76 [10] 2403-18 (1993). [12] P. Su and A. V. Virkar, “Ionic Conductivity and Phase Transformation in Gd2O3-Stabilized Bi2O3,” J. Electrochem. Soc., 139[6], June. 1671-7 (1992). [13] P. Su and A. V. Virkar, “Cubic-to-Tetragonal Displacive Transformation in Gd2O3-Bi2O3 Ceramics,” J. Am. Ceram. Soc., 76 [10] 2513-20 (1993). [14] T. Ishihara, H. Matsuda, and Y. Takita, “Doped LaGaO3 Perovskite Type Oxide as a New Oxide Ionic Conductor,” J. Am. Chem. Soc. 116, 3801-3 (1994). [15] N. Q. Minh, “Ceramic Fuel Cells,” J. Am. Ceram. Soc. 76 [3] 563-88 (1993). [16] N. M. Sammes, “The Fracture Toughness of Doped Bismuth Oxide Electrolytes,” J. Mater. Sci. Letters, 12[10] 719-20 (1993). [17] I. C. Cosentino, and R. Muccillo, “The Effect of Bismuth Oxide Addition on the Electrical Properties of Zirconia-Magnesia Solid Electrolytes,” J. Mater. Sci. Letters, 38[4] 511-7 (1993). [18] T. Ishihara, H. Matsuda, and Y. Takita*, “Doped LaGaO3 Perovskite Type Oxide as a New Oxide Ionic Conductor,” J. Am. Chem. Soc., 116, P.3801-3 (1994). [19] J.B. Goodenough, A. Manthiram and J. F. Kuo, “Oxygen Diffusion in Perovskite-Related Oxides,” Mater. Chem. and Phy., 35, P.221-4 (1993). [20] P. N. Huang, and A. Petric, “Superior Oxygen Ion Conductivity of Lanthanum Gallate Doped with Strontium and Magnesium,” J. Electrochem. Soc., 143[5], May (1996). [21] A. A. Agasiev and Y. Y. Guseinov, “Peculiarities of Photoelectrical Properties of Bismuth Oxide Films,” Phys. Stat. Sol. (a) 136, P.473-82 (1993). [22] B. A. Boukamp, B. A. V. Hassel, I. C. Vinke, K. J. De Vries, and A. J. Burggraaf, “The Oxygen Transfer Process On Solid Oxide/Noble Metal Electrodes, Studied With Impedance Spectroscopy, Dc Polarization and Isotope Exchange,” Electrochimica Acta, 38[14] 1817-25 (1993). [23] I. Kanazirski, M. Bojinov, and A. Girginov, “Electrical Properties of The Barrier Layer/Solution Interface and Its Role During Breakdown of Anodic Bismuth Oxide Films,” Electrochimica Acta, 38[4] 515-17 (1993). [24] M. G. Norton, E.S. Hellman and E.H. Hartford Jr., and C.B. Carter, “Compositionally Modulated Nucleation and Growth of Barium Bismuth Oxide Thin Films On MgO,” Physica C, 205,.347-53 (1993). [25] 鄭煜騰, “燃料電池用重組器設計要點及新發展,” 能源季刊, 二十三卷第三期, 107-8,八十二年七月. [26] 張蕙芳, “二十一世紀的發電技術-燃料電池,” 能源季刊, 二十三卷第四期, 64-78 , 八十二年十月. [27] 鄭耀宗, 吳龍暉譯, “世界各國燃料電池技術發展現況,” 能源季刊, 第二十一卷第三期, 83-98, 八十年七月. [28] 鄭耀宗, 楊正光, 蘇華宗, “燃料電池發電技術的發展與推廣,” 能源季刊, 第二十五卷第三期, 158-160, 八十四年七月. [29] 黃銘賢, “陶磁燃料電池 SOFC,” 能源季刊, 第二十六卷第四期, 117-127, 八十五年十月.

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chi[[iso]]en_US

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thesis

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燃料電池

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碩博士論文

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