本研究以LaAlO3為主，以硝酸鑭及硝酸鋁為起使原料，藉由添加檸檬酸鏊合金屬離子，探討[金屬] / [檸檬酸]比和煆燒氣氛（空氣或氧氣氛）、溫度與時間對金屬檸檬酸鹽先驅物熱解製得結晶LaAlO3奈米粉體的影響。研究中利用熱重分析/熱差分析儀(TGA /DTA)的結果來判別在不同煆燒氣氛下的熱行為，且以傅氏轉換紅外線光譜儀（FT-IR）與X-光線繞射分析(XRD)結果來探討鋁酸鑭的成相過程。並利用掃瞄式電子顯微鏡(SEM)與穿透式電子顯微鏡(TEM)來觀察粉末形態。
當[檸檬酸]/[金屬]=2.25(CA2.25)且不添加氨水的系統中，經過350℃熱處理之後，鑭離子和鋁離子會形成LaAl(OOCH2)3的鍵結，而起始溶液添加氨水則會形成LaAlO3-x(CO3)x(s)。當檸檬酸量的減少[檸檬酸]/[金屬]=0.5 (CA0.5)，可降低碳酸根的含量，其熱行為與CA2.25相似；但兩系統皆需煆燒≥ 800℃才能移除殘留的焦碳得到純的LaAlO3。熱處理時，在氧氣氛下可降低結構中的氧空缺，使結晶峰的溫度提前，促使CA0.5 pH7檸檬酸鹽固態先驅物在氧氣氛下550℃ 3小時後即可得結晶的LaAlO3。顯結構分析顯示，不添加氨水時，減少檸檬酸的添加有助於減少塊體凝聚的現象；添加氨水時，檸檬酸過量系統呈現塊狀，且較為緊密，CA0.5則較為鬆散。隨著氨水的添加量增加有助於縮小粉體晶粒尺寸。

The reaction mechanisms for forming pure LaAlO3 from the citrate-precursors, being derived from the aqueous solutions containing La(NO3)3, Al(NO3)3, and C3H4(OH)(COOH)3 in different molar ratio at different pH conditions, and effects of atmosphere、temperature and time of calcination, were investigated using x-ray diffractometry, infrared spectroscopy, thermogravimetric analysis, and differential thermal analysis. The particle size and morphology of LaAlO3 powder were observed using scanning electron microscopy and transmission electron microscopy. 
At 350 oC, the lanthanum and aluminum elements were bonded together in forms of LaAl(OOCH2)3 for no NH4OH additions and LaAlO3-x-y(CO3)x(OH)2y for adding NH4OH in the starting solution. The specimen derived using [Citric Acid]/[Metallic ions]=0.5(CA0.5) has less cher formation than those using [Citric Acid]/[Metallic ions]=2.25(CA2.25), and the thermochemical behavior for different citric acid additions are similar. However, calcining the specimens at ≥ 800 oC were required to remove all residual chars in air atmosphere to form pure LaAlO3. When calcined in oxygen the specimens may contain less amount of oxygen vacancies in the structure, which make the citrate-precursor CA0.5 pH7 can form crystalline LaAlO3 at 550℃ for 3hr. From the SEM and TEM observations, the powder obtained by adding NH4OH has a less degree of particle agglomeration than that obtained without NH4OH addition.The grain size of LaAlO3 decrease with the NH4OH additions, for the powder calcined at 900℃ for 3 h.

目 錄
                                                       頁次
中文摘要	Ⅰ
英文摘要	Ⅱ
目 錄	Ⅲ
圖 目 錄	Ⅴ
表 目 錄	Ⅸ
第一章 緒論	1
第二章 基礎理論與文獻回顧	4
2-1 LaAlO3的基本性質	4
2-2文獻回顧	6
第三章 實驗步驟及方法	15
3-1實驗製程	15
3-1.1實驗所需之試藥...............................................................15
3-1.2實驗步驟...........................................................................15
3-2儀器分析與操作狀態	19
3-2.1熱分析儀	19
3-2.2 X光繞射分析	23
3-2.3傅氏轉換紅外線光譜儀	26
3-2.4掃瞄式電子顯微鏡	28
3-2.5穿透式電子顯微鏡	30
第四章 結果與討論	31
4-1  [檸檬酸] / [金屬離子]＝2.25	31
4-1.1不添加NH4OH對合成LaAlO3機制的影響	31
4-1.2 pH值對檸檬酸鹽合成LaAlO3的影響	34
4-2 [檸檬酸]/[金屬離子]比例的影響	43
4-3 [檸檬酸] / [金屬離子]＝0.5	48
4-3.1不添加NH4OH對合成LaAlO3機制的影響	48
4-3.2 pH值對檸檬酸鹽合成LaAlO3的影響	50
4-4煆燒氣氛的影響	57
4-5熱處理溫度與時間的影響	77
4-6粉末的顯微結構分析	80
第五章 結論	97
參考文獻	98
 
圖 目 錄
                                                       頁次
圖2-1鈣鈦礦結構	4
圖3-1檸檬酸鏊合法備製LaAlO3粉末的實驗流程圖.	17
圖3-2三種基本熱重量法示意圖	21
圖3-3 DTA的(a)放熱反應測試圖與(b)吸熱反應測試結.	22
圖3-5水分子的三種基本振動模式.	27
圖3-6掃描式電子顯微鏡剖面機構示意圖.	29
圖4-1.1 CA2.25 pH2 TG/DTA分析.	36
圖4-1.2 CA2.25 pH2 不同溫度下 FTIR圖.	37
圖4-1.3 CA2.25 pH2 不同溫度下 XRD圖…38
圖4-1.4 CA2.25 不同pH值 TG/DTA分析.	39
圖4-1.5 CA2.25 pH=9時不同熱處理溫度的IR圖	40
圖4-1.6 CA2.25 pH=9時不同熱處理溫度的XRD圖.	41
圖4-2.1(a) CA2.25 不同pH值 煆燒600℃ 9小時 IR圖	45
圖4-2.1(b) CA2.25 不同pH值 煆燒600℃ 9小時 XRD圖	45
圖4-2.2(a) CA1 不同pH值 煆燒600℃ 9小時 IR圖	46
圖4-2.2(b) CA1 不同pH值 煆燒600℃ 9小時 XRD圖	46
圖4-2.3(a) CA0.5 不同pH值 煆燒600℃ 9小時 IR圖	47
圖4-2.3(b) CA0.5 不同pH值 煆燒600℃ 9小時 XRD圖	47
圖4-3.1 CA0.5 pH2 TG/DTA分析	52
圖4-3.2 CA0.5 pH2加熱處理後之IR圖	53
圖4-3.3 CA0.5 不同pH值之溶液狀態	54
圖4-3.4 CA0.5 不同pH值前驅物粉體IR圖	55
圖4-3.5 CA0.5 不同pH值 TG/DTA分析	56
圖4-4.1 CA0.5 pH7固態先驅物在空氣氣氛與氧氣氣氛下煆燒   600℃ XRD圖	61
圖4-4.2 (a) CA2.25 pH2 空氣氣氛與氧氣氣氛下 TG/DTA分析	62
圖4-4.2 (b) CA2.25 pH7 空氣氣氛與氧氣氣氛下 TG/DTA分析	63
圖4-4.2 (c) CA2.25 pH9 空氣氣氛與氧氣氣氛下 TG/DTA分析	64
圖4-4.2 (d) CA0.5 pH2 空氣氣氛與氧氣氣氛下 TG/DTA分析	65
圖4-4.2 (e) CA0.5 pH7 空氣氣氛與氧氣氣氛下 TG/DTA分析	66
圖4-4.2 (f) CA2.25 pH9 空氣氣氛與氧氣氣氛下 TG/DTA分析	67
圖4-4.3 CA0.5 pH7空氣氣氛與氧氣氣氛下不同熱處理溫度 IR圖	68
圖4-4.4 CA0.5 pH7空氣氣氛與氧氣氣氛下煆燒粉體之XRD圖	69
圖4-4.5 CA0.5 pH7空氣氣氛與氧氣氣氛下煆燒粉體之IR圖	70
圖4-4.6 不同檸檬酸添加量，在氧氣氛下煆燒 XRD圖	71


圖4-4.7(a) CA2.25不同pH值 空氣氣氛與氧氣氣氛下煆燒900℃    3小時 XRD圖	72
圖4-4.7 (b) CA2.25不同pH值 空氣氣氛與氧氣氣氛下煆燒900℃
       3小時 IR圖………..…………………………………………73
圖4-4.8(a) CA0.5不同pH值  空氣氣氛與氧氣氣氛下煆燒900℃    3小時 XRD圖	74
圖4-4.8(b) CA2.25不同pH值 空氣氣氛與氧氣氣氛下煆燒900℃    3小時 IR圖	75
圖4-4.9改變檸檬酸的比在空氣氣氛與氧氣氣氛下煆燒900℃       3小時，其晶粒尺寸對氨水添加量之影響	76
圖4-5.1 CA0.5 pH7在氧氣氛下煆燒 XRD圖	78
圖4-5.2 CA0.5 pH7在氧氣氛下煆燒 IR圖	79
圖4-6.1 不添加氨水時 (pH2) 不同檸檬酸比在氧氣氛煆燒900℃  持溫3小時後所得粉體的SEM圖，放大倍率為5,000	84
圖4-6.2 不添加氨水時 (pH2) 不同檸檬酸比在氧氣氛煆燒900℃  持溫3小時後所得粉體的SEM圖，放大倍率為50,000	84
圖4-6.3 CA2.25添加氨水在氧氣氛煆燒900℃持溫3小時後所得    粉體的SEM圖，放大倍率為5,000	85


圖4-6.4 CA2.25添加氨水在氧氣氛煆燒900℃持溫3小時後所得    粉體的SEM圖，放大倍率為50,000	85
圖4-6.5 CA0.5添加氨水在氧氣氛煆燒900℃持溫3小時後所得     粉體的SEM圖，放大倍率為5,000	86
圖4-6.6 CA0.5添加氨水在氧氣氛煆燒900℃持溫3小時後所得     粉體的SEM圖，放大倍率為50,000	86
圖4-6.7 CA0.5 pH7在氧氣氛煆燒不同溫度的SEM圖，            放大倍率為5,000	87
圖4-6.8 CA0.5 pH7在氧氣氛煆燒不同溫度的SEM圖，            放大倍率為50,000	88
圖4-6.9 CA0.5 pH7在空氣氛煆燒900℃ 3小時不同放大倍率的   SEM圖	89
圖4-6.10 CA2.25不同pH值下 氧氣氣氛煆燒900℃ 3小時      TEM圖	92
圖4-6.11 CA2.25不同pH值下 空氣氣氛煆燒900℃ 3小時      TEM圖	93
圖4-6.12 CA0.5不同pH值下 氧氣氣氛煆燒900℃ 3小時       TEM圖	94


圖4-6.13 CA0.5不同pH值下 空氣氣氛煆燒900℃ 3小時       TEM圖	95
圖4-6.14 CA0.5 pH7在氧氣氛下煆燒3小時之溫度對粒徑關係圖
	96
表 目 錄
                                                       頁次
表1-1微波介電材料特性影響	2
表3-1實驗所需試藥.	15
表3-2儀器分析目的及操作狀態	18
表3-3 XRD應用所提供相對應資訊	25
表3-4光區與相對應之波長範圍.	26
表4-1檸檬酸鹽先驅物粉體經加熱後所測量到的值與重量的變化   的計算	42

參考文獻
1.	Okaya: Proc. IRE, vol.48, p.1921 (1960).
2.	H. M. O’Brryan, JR. and J. Thomson, JR.: J.Am.Ceram.Soc.vol.57, p.450 (1974).
3.	G.Wolfram and H.E.Gobel: Mat.Res.Bull. vol.16, p. 1455 (1981).
4.	S. Nishgaki, H. Kato, S. Yano and R. Kamamura: Am.Ceram. Soc. Bull.,vol.66, p.1405, (1987).
5.	 S.B.Chon,“Microwave Bandpass Filters Containg High Q Dielectric Resonator”, IEEE Trans. On MTT,MTT, p.218 (1968).
6.	H. Ouchi and S. Kawashima: Pro. of the 6th meeting on Ferroelectricity, Kobe , Jpn. J. Appl. Phys.,vol.24, p.60 (1985).
7.	T. Tagawa, and H. Imai, “Mechanistic aspects of oxidative coupling of methane over LaAlO3.” J. Chem. Soc., Faraday Trans. 1. Phys. Chem. Condens. Phases, 84 [4] 923-929 (1988).
8.	S.S. Shoup, M. Paranthaman, D.B. Beach, E.D. Specht and R.K. Williams, “Sol-gel synthesis of LaAlO3; epitaxial growth of LaAlO3 thin films on SrTiO3 (100)” J. Mater. Res. 12[4] 1017-1021 (1997).
9.	S.-Y. Cho, I.-T. Kim and K.S. Hong, “Microwave dielectric properties and applications of rare-earth aluminates.” J. Mater. Res., 14[1] 114-119 (1999).
10.	D.A. Atwood and B.C. Yearwood, “The future of aluminum chemistry.” J. Organomet. Chem., 600 186-197 (2000).
11.	C.-S. Hsu and C.-L. Huang. “Effect of CuO additive on sintering and microwave dielectric behavior of LaAlO3 ceramics.” Mater. Res. Bull., 36 1939-1947 (2001).
12.	M. Nieminen, T. Sajavaara, E. Rauhala, M. Putkonen and L. Niinistö, “Surface-controlled growth of LaAlO3 thin films by atomic layer epitaxy.” J. Mater. Chem., 11[12] 2340-2345 (2001).
13.	J.-L. Tang, J. Zhu, W.-F. Qin, J. Xiong, Y. Zhang and Y.-R. Li, “Atomic relaxation and electronic redistribution of LaAlO3(001) surfaces.” Physics Letters., 365 149-155 (2007).
14.	H. Choi, M. Chang, M. Jo, S.-J. Jung, and H. Hwang “Improved Memory Characteristics of Ge Nanocrystals Using a LaAlO3 Buffer Layer.” Electrochem. Solid-State Lett., 6 154-156 (2008)
15.	李春穎 許煙明 陳忠仁合譯, 材料科學與工程, 高立圖書有限公司
16.	S.Y. Cho, I.-T. Kim and K.S. Hong, “Microwave dielectric properties and applications of rare-earth aluminates.” J. Mater. Res., 14 [1] 114-119 (1999)
17.	G.Y. Sung, K.Y. Kang and S.C. Park, “Synthesis and preparation of lanthanum aluminate target for radio-frequency magnetron sputtering.” J. Am. Ceram. Soc., 74[2] 437-439 (1991)
18.	R. Elsebrock, C. Makovicka, P. Meuffels and R. Waser, “Preparation and characterisation of high density, high purity lanthanum aluminate bulk ceramics.” J. Electroceram., 10 193-202 (2003).
19.	T.A. Vanderah, C.K. Lowe-Ma and D.R. Gagnon, “Synthesis and dielectric properties of substituted lanthanum aluminate.” J. Am. Ceram. Soc., 77 [12] 3125-3130 (1994).
20.	M. Kakihana and T. Okubo, “Low temperature powder synthesis of LaAlO3 through in situ polymerization route utilizing citric acid and ethylene glycol.” J. Alloys and Comp., 266 129-133 (1998).
21.	C.H. Kim, J.W. Jang, S.Y. Cho, I.T. Kim and K.S. Hong, ”Ferroelastic twins in LaAlO3 Polycrystals,” Physica B262 438-443 (1999).
22.	C.-L. Kuo, C.-L. Wang, T.-Y. Chen, G.-J. Chen, I.-M. Hung, C.-J. Shih and K.-Z. Fung, “Low temperature synthesis of nanocrystalline lanthanum monoaluminate powders by chemical coprecipitation.” J. Alloys Comp., 440 367-374 (2007).
23.	W. Li, M.W. Zhuo and J.L. Shi, “Synthesizing nano LaAlO3 powders via co-precipitation method.” Mater. Lett., 58 365-368 (2004).
24.	P.K. Sahu, S.K. Behera, S.K. Pratihar and S. Bhattacharyya, “Low temperature synthesis of microwave dielectric LaAlO3 nanoparticles: effect of chloride on phase evolution and morphology.” Ceram. Int., 30 1231-1235 (2004).
25.	E.a. Taspinar, and A.C. Tas, “Low-temperature chemical synthesis of lanthanum monoaluminate” American Ceram Society., 80 133-141 (1997). 
26.	M. Chroma, J. Pinkas, I. Pakutinskiene, A. Beganskiene and A. Kareiva, “Processing and characterization of sol-gel fabricated mixed metal aluminates.” Ceram. Int., 31 1123-1130 (2005).
27.	S.N. Koc, F. Oksuzomer, E. Yasar, S. Akturk and M.A. Gurkaynak, “Effect of sol-gel modifications on formation and morphology of nanocrystalline lanthanum aluminate.” Mater. Res. Bull., 41 2291-2297 (2006).
28.	A.K. Adak and P. Pramanik, “Synthesis and characterization of lanthanum aluminate powder at relatively low temperature.” Mater. Lett., 30 269-273 (1997).
29.	Q. Zhang and F. Saito “Mechanochemical synthesis of lanthanum aluminate by grinding lanthanum oxide with transition alumina.” J. Am. Ceram. Soc., 83 [2] 439-441 (2000). 
30.	Z. Li, S. Zhang and W.E. Lee, “Molten salt synthesis of LaAlO3 powder at low temperatures.” J. Europ. Ceram. Soc., 27 3201-3205 (2007).
31.	Q.X. Fu, F. Tietz, P. Lersch and D. Stöver, “Evaluation of Sr- and Mn-substituted LaAlO3 as potential SOFC anode materials.” Solid State Ionics., 177 1059-1069 (2006).
32.	D. Zhou, G. Huang, X. Chen, J. Xu and S. Gong, “Synthesis of LaAlO3 via ethylenediaminetetraacetic acid precursor.” Mater. Chem. Phys., 84 33-36 (2004).
33.	Z.Q. Tian, H.T. Yu and Z.L. Wang, “Combustion synthesis and characterization of nanocrystalline LaAlO3 powders”, Materials Chemistry and Physics., 106 126–129 (2007)
34.	 Z.Q. Tian, H.T. Yu, Z.L. Wang and W.J. Huang,  “Synthesis of LaAlO3 by Glycine-Nitrate Process and microwave dielectric properties”,  Yadian Yu Shengguang/Piezoelectrics and Acoustooptics., 29 689-691 (2007) 
35.	S. Ran and L. Guo, “Synthesis of LaAlO3 powder using triethanolamine”,  Ceram. Int., 34 443-446 (2008)
36.	W. Wm. Wendlandt, Thermal Analysis 1st, 13 (1992)
37.	J. Paulik, F. Paulik, and L. Erden,；Hungarian Patent 152197 (1962)
38.	J. Paulik and F. Paulik,；Thermochim. Acta., 100, 23, (1986)
39.	T.P. Bagchi and  P.K. Sen, Thermochim Acta, 70 363 (1983)
40.	W.L. Bragg, “The Diffraction of Short Electromagnetic Waves by a Crystal”, Proceedings of the Cambridge Philosophical Society., 17 43–57 (1914)
41.	汪建民主編，材料分析，中國材料科學學會，(1998)
42.	A.L. Patterson, “The Scherrer formula for X-ray particle size determination”, Phys. Rev. 56, 978–982 (1939)
43.	鄭信民、林麗娟, “X光繞射應用簡介”, 工業材料雜誌 181期
44.	張喜寧、夏鎮洋合譯, “穿透式及掃瞄式電子顯微鏡生物技術”, 國立編譯館
45.	楊永盛、楊慶宗編著, “電子顯微鏡原理與應用”, 文京圖書有限公司
46.	陳季南、周釗生“穿透式電子顯微鏡在半導體製程之應用”, 電子月刊第三卷第三期(1997)
47.	Socrates, G, Infrared and Raman Characteristic Group Frequencies Tables and Charts, 3rd ed., Wiley, Chichester, UK, (2001)