本研究以固態反應法合成製備鍶摻雜鍺酸鑭基磷灰石電解質材料，藉由添加不同成分的 Sr2+ 取代 La10-xSrxGe6O27-x/2 中的 La 位置 (x= 0、0.25、0.5、0.75、1、1.25)，觀察其在高溫時的晶體結構與導電性質之關聯性。
實驗結果顯示隨著鍶添加量的增加，當 x= 1.5 時已出現二次相，推測已超出固溶範圍，故 La10-xSrxGe6O27-x/2 的固溶範圍約為 1.25，而在固溶範圍內之其他成分點皆可以在煅燒條件為 1300°C/3 h 合成出單一相。隨後以 1400°C/3 h 以及 1450°C/3 h 進行燒結，各成分點之燒結體相對密度皆可達到 95% 以上，並無二次相生成，且所有成分點微結構皆相似，而在 X = 1.25 時擁有最高的導電度。接下來將燒結體進行高溫 XRD 分析，並以 Rietveld refinement method 精算出不同溫度環境之下的晶格常數，再繪製出各成分點之晶體結構，藉此來觀察間隙氧離子在結構內傳遞的空間大小變化與導電率之間之關聯。最後進行陶瓷體熱膨脹係數的量測，量測各個成分點在 100 800°C 的熱膨脹係數，藉此來觀察是否適合作為固態氧化物燃料電池的電解質材料，並利用Rietveld refinement method 所得到的晶格常數計算出各個成分點的晶體熱膨脹係數，並將晶體熱膨脹係數與陶瓷體熱膨脹係數進行比較。

In recent years, owing to rising awareness of environmental protection, people are committed to developing renewable and non-polluting alternative energy. The solid oxide fuel cells (SOFCs) are the most promising fuel cell materials due to their high efficiency and low pollution levels. The apatite structures have the highest conductivity of all the solid oxide fuel cell (SOFC) electrolytes because of their conduction mechanism. Among all the apatite-type electrolytes, lanthanum-germanate possess the highest conductivity. The main purpose of this study is to observe the relationship between composition, crystal structure and ionic conductivity by doping different content Sr2+ into the La3+ sites. Since Sr2+ ion has larger ionic radii than La3+ ion, crystal structure has been distorted which makes interstitial oxygen can be migrated easily. Consequently, a series of strontium-doped lanthanum-germanate apatite-type materials, La10-xSrxGe6O27-x/2 (x=0, 0.25, 0.5, 0.75, 1, 1.25) were prepared in an attempt to synthesize a single phase by solid-state reaction method. The XRD pattern showed that a single phase could be obtained for all compositions calcined at 1300℃/3 h. And the sintered bodies have high relative density after sintering at 1400℃/3 h and 1450℃/3 h. Then I conduct the high-temperature XRD analysis, and use the Rietveld refinement method to conduct crystal structure analysis. In order to observe the relationship between the conductivity and the migration opening of the interstitial oxygen. Finally, I measure the thermal expansion coefficient, in order to observe whether this material has a compatible thermal expansion coefficient with the anode and cathode. And I compare the thermal expansion coefficient of crystal structure and thermal expansion coefficient of sintered bodies.

1.台灣電力公司，電源開發計畫，台北，經濟部，2018。
2.S. Nakayama, T. Kageyama, H. Aono and Y. Sadaoka, “Ionic conductivity of lanthanoid silicates, Ln10(SiO4)6O3 (Ln = La, Nd, Sm, Gd, Dy, Y, Ho, Er and Yb).” Journal of Materials Chemistry, 5(11), 1801-1805, 1995.
3.H. Arikawa, H. Nishiguchi, T. Ishihara and Y. Takita, “Oxide ion conductivity in Sr-doped La10Ge6O27 apatite oxide. ” Solid State Ionics, 136, 31-37, 2000.
4.發行人葉惠青 (2010)，2010能源產業技術白皮書，台北：經濟部能源局，第 341 頁。
5.台灣燃料電池夥伴聯盟，財團法人台灣經濟研究院版權所有。 FC介紹。2013年11月5日，取自台灣燃料電池資訊網。
6.陽哲化，固態氧化物燃料電池 (SOFC) 原理與檢測，國立台北科技大學製造科技所，中華民國九十五年。
7.曾儒雅、黃啟原，「鈮摻雜對鍺酸鑭基磷灰石電解質晶體結構之研究」，國立成功大學資源工程所碩士論文，2012。
8.林鈺烜、黃啟原，「鎳摻雜之鍺酸鑭基磷灰石離子導體之晶體結構與電性」，國立成功大學資源工程所碩士論文，2015。
9.http://www.chinabaike.com/article/316/327/2007/2007022260477.html.
10.J. C. Diniz da Costa, “Mixed ionic-electronic conducting (MIEC) ceramic-based membranes for oxygen separation,” Journal of Membrane Science, 320(1), 13-41, 2008.
11.S. Nakayama, Y. Higuchi, Y. Kondo, and M. Sakamoto, “Effects of cation- or oxide ion-defect on conductivities of apatite-type La–Ge–O system ceramics,” Solid State Ionics, 170, pp. 219~223, 2004.
12.D. Elbio, H. Takashi and M. Adriana, “Colossal magnetoresistant materials: the key role of phase separation,” Physics Reports, 344(1), 1-153, 2001.
13.S. Nakayama, H. Aono and Y. Sadaoka, “Ionic conductivity of Ln10(SiO4)6O3 (Ln = La, Nd, Sm, Gd and Dy),” Chemistry Letters, 24, pp. 431-432, 1995.
14.S. Nakayama, T. Kageyama, H. Aono and Y. Sadaoka, “Ionic conductivity of lanthanoid silicates Ln10(SiO4)6O3 (Ln = La, Nd, Sm, Gd, Dy, Y, Ho, Er and Yb),” Journal of Materials Chemistry, 5, pp. 1801-1805, 1995.
15.S. Nakayama and M. Sakamoto, “Electrical properties of new type high oxide ionic conductor RE10Si6O27 (RE = La, Pr, Nd, Sm, Gd, Dy),” Journal of the European Ceramic Society, 18, pp. 1413-1418, 1998.
16.M. Higuchi, Y. Masubuchi, S. Nakayama, S. Kikkawa and K. Kodaira, “Single crystal growth and oxide ion conductivity of apatite-type rare-earth silicates.” Solid State Ionics, 174(1), 73-80, 2004.
17.J. R. Tolchard, M. S. Islam and P. R. Slater, “Defect chemistry and oxygen ion migration in apatite-type materials La9.33Si6O26 and La8Sr2O26.” Journal of Materials Chemistry, 13(8), 1956-1961, 2003.
18.S. Nakayama, M. Sakamoto, M. Higuchi, K. Kodaira, M. Sato, S. Kakita, T. Suzuki and K. Itoh, “Oxide ionic conductivity of apatite type Nd9.33(SiO4)6O2 single crystal.” Journal of The European Ceramic Society, 19(4), 507-510, 1999.
19.L. Leon-Reina, J. Manuel Porras-Vazquez, Enrique R. Losilla, and Miquel A. G. Aranda, “Interstitial oxide positions in oxygen-excess oxy-apatites,” Solid State Ionics, 177, pp. 1307~1315, 2006.
20.S. F. Wang, Y. F. Hsu, W. J. Lin, K. Kobayashi, “Transition metal-doped lanthanum germanate apatites as electrolyte materials of solid oxide fuel cells,” Solid State Ionics, 176, 1941-1947, 2013.
21.H. Yanagida, K. Koumoto, and M. Miyayama, The Chemistry of Ceramics. 1996, pp. 185-190.
22.D. W. Richerson, Modern Ceramic Engineering (3rd ed.). 2006, pp. 198-207.
23.E. V. Tsipis, and V. V. Kharton, “Electrode materials and reaction mechanisms in solid oxide fuel cells: a brief review,” Journal of Solid State Electrochem, pp. 1367-1391, 2008.
24.R. A. Young, “The Rietveld Method.” International Union of Crystallography, 21-26, 1993.
25.W. Liu, S. Yamaguchi, T. Tsuchiya, S. Miyoshi, K. Kobayashi and W. pan, “Sol-gel synthesis and ionic conductivity of oxyapatite-type La9.33+xSi6O26+1.5x.” Journal of Power Sources, 235, 62-66, 2013.
26.林立武、黃啟原，「鎢摻雜之鍺酸鑭基磷灰石離子導體之晶體結構與電性」，國立成功大學資源工程所碩士論文，2014。
27.P. R. Slater, J. E. H. Sansom and J. R. Torchard, “Development of apatite-type oxide ion conductors.” Chemical Record, 4(6), 373-384, 2004.