跳到主要內容

臺灣博碩士論文加值系統

(44.201.97.224) 您好!臺灣時間:2024/04/14 18:18
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:魏宇晨
研究生(外文):Yu-Chen Wei
論文名稱:高效能直接甲醇燃料電池陽極觸媒之製備、改質與鑑定研究
論文名稱(外文):Preparation, Modification and Characterization of High Performance Anode PtRu/C Catalyst in Direct Methanol Fuel Cell
指導教授:王冠文王冠文引用關係
指導教授(外文):Kuan-wen Wang
學位類別:碩士
校院名稱:國立中央大學
系所名稱:材料科學與工程研究所
學門:工程學門
學類:綜合工程學類
論文種類:學術論文
論文出版年:2008
畢業學年度:96
語文別:英文
論文頁數:86
中文關鍵詞:氧化釕氧化鈰合金化直接甲醇燃料電池鉑釕陽極觸媒甲醇電催化反應
外文關鍵詞:Direct methanol fuel cellMetPtRu/C catalysts
相關次數:
  • 被引用被引用:0
  • 點閱點閱:302
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
直接甲醇燃料電池(DMFC)具有體積小、工作溫度低且易於貯存與處理的優點,但也有諸如較低的功率密度、陽極白金觸媒易遭一氧化碳毒化、甲醇穿透(crossover)與觸媒價格相對高等缺點,因此在產業界與學術界皆有許多關於提升觸媒效能的研究。本研究採用沉澱沉積法(deposition precipitation, DP)製備重量組成比是Pt : Ru : C = 13.4 : 6.6 : 80之鉑釕陽極觸媒(PtRu/C)。結合氧化鈰修飾劑(CeO2)和不同熱處理等改質方式,製備出甲醇氧化效能超越商用材之優良觸媒。

所製備的觸媒,以X光繞射分析儀(X-ray diffraction, XRD)量測其結構,並以程式溫度還原系統(temperature-programmed reduction, TPR)分析其表面組成,而電催化特性則以電化學循環伏安法(cyclic voltammetry, CV)分析。結果顯示;添加10 wt%氧化鈰因增加了PtRu合金的分散度而增加觸媒活性。然則過多的氧化鈰可能包覆觸媒反而降低觸媒反應活性。比較I05 (0.5V vs. NHE)可發現,觸媒經適當氮氣熱處理(520 ~ 570 K)樣品之氧化電流較氧氣熱處理樣品為高。從XRD分析發現,過高的熱處理溫度導致觸媒顆粒變大及PtRu相分離而使活性下降。TPR分析表面組成顯示經氮氣熱處理後PtRu/C觸媒合金化程度增加,表面主要物種為Pt;而氧氣熱處理後,合金相分離表面產生Pt和RuO2。由上述實驗結果可知,觸媒表面組成為Pt而非RuO2,為具有高甲醇氧化活性之重要關鍵。
The direct methanol fuel cell (DMFC) has many advantages, such as the small size, low working temperature, and easy fuel-feeding. However, it also has some disadvantages, for example, low power density, Pt poison by CO, methanol crossover, and high cost for catalysts. Therefore, many researchers have focused on the study of performance enhancement for catalysts. In this study, PtRu/C alloy catalysts with a weight ratio of Pt : Ru : C = 13.4 : 6.6 : 80 have been prepared by the deposition precipitation method (DP). The modification of the PtRu/C catalysts by combination of addition of CeO2 promoter and different heat treatments has been studied to increase its electrochemical activities of methanol oxidation reaction.

For the prepared catalysts, the phase structure was analyzed by X-ray diffraction (XRD). The surface species was measured by temperature-programmed reduction (TPR). The electro-oxidation performance was studied by cyclic voltammetry (CV). CV results showed that the the promotion of the catalytic activity by an addition of 10 wt% CeO2 was attributed to the enhancement of dispersion for PtRu crystallites. However, for the PtRu/Ce20C samples, much amount of CeO2 resulted in the decrease of the catalytic activity. The N2- treated samples (520 ~570 K) exhibited better methanol oxidation current at I05 than air heated ones. XRD analysis illustrated that the large particle size and the phase separation of PtRu alloys caused by the severe heat treatment and led to the deterioration of catalytic activity. TPR characterization revealed that the surface species for N2-treated and air-treated catalysts was Pt and Pt+RuO2, respectively. The N2 treatment can increase the degree of alloying for the catalysts while air treatment resulted in the formation of RuO2 and sintering of Pt. It suggested that an alloy surface with a Pt surface species rather than RuO2 are essential to high I05 for methanol oxidation current.
中文摘要………………………………………………………… i
Abstract………………………………………………………… ii
致謝……………………………………………………………… iv
List of figures………………………………………………… ix
List of tables…………………………………………………… xii
Chapter I Introduction…………….…………………… 1
1. History of fuel cells …………………………………… 2
2. Classification of fuel cell …………………………… 2
3. Structure of fuel cell …………………………………… 6
3.1 Proton exchange membrane ……………………………… 6
3.2 Gas diffusion layers …………………………………… 10
3.3 Catalyst layers ………………………………………… 10
Chapter II Literature Review …………………………… 11
1. Principle of DMFC………………………………………… 11
2. Catalysts in DMFC………………………………………… 18
2.1 Mechanism of methanol oxidation …………………… 18
2.2 Anode catalysts of DMFC………………………………… 19
3. Motivation in this study……………………………………26
Chapter III Experimental procedures……………………… 27
1. Preparation of catalysts………………………………… 27
1.1 Deposition-precipitation method……………………… 27
2. Heat treatment of catalysts…………………………… 27
3. Characterization of catalysts…………………… 27
3.1 X-ray diffraction (XRD) ………………………………… 29
3.2 Transmission electron microscopy (TEM) …………… 29
3.3 Inductive coupled plasma on atomic emission spectrometry (ICP-AES) ……………………………………… 29
3.4 Temperature programmed reduction (TPR) …………… 31
3.5 Electrochemical measurements (CV) ………………… 31
Chapter IV Results and Discussion……………………… 35
1. XRD characterization……………………………………… 35
1.1 XRD characterization of the as-reduced and
heat-treated PtRu/C catalysts ………………………… 35
1.2 XRD characterization of the as-reduced and
heat-treated PtRu/Ce10C catalysts …………………… 40
1.3 XRD characterization of the as-reduced and
heat-treated PtRu/Ce20C catalysts …………………… 43
2. Electrochemical performance of PtRu/CexC …………… 47
2.1 Promotion of CeO2 to PtRu/C catalysts … 47
2.2 Promotion of PtRu/CexC by different heat treatments ……………………………………………… 48
3. TPR characterization of PtRu/CexC catalysts……… 62
4. TEM characterization of PtRu/CexC catalysts……… 77
Chapter V Conclusions ………………………………… 80
Chapter VI Future Work…………………………………… 81
Chapter VII Reference …………………………………… 82
[1] K. Kordesch and G. Simader, “Fuel cells and their applications”, CRC Press LLC, 2002.
[2] P. B. L Chaurasia, Y. Ando, and T. Tanaka, Energy Conversion and Management, 2003, 44, 611.
[3] S. Song, Catalyst Today, 2002, 77, 17.
[4] G. J. K Acres, J. Power Sources, 2001, 100, 60.
[5] P. Costamagna and S. Srinvasan, J. Power Sources, 2001, 102, 242.
[6] V. A. paganin, C. L. F. Oliveira, E. A. Ticianelli, T. E. Springer, and
E. R. Gonzalez, Electrochimica Acta, 1998 , 43, 3761.
[7] G. Hoogers, “Fuel cell technology”, CRC Press, New York and London, 2002.
[8] W. Vielstich and J. Braz, Chem. Soc., 2003, 14, 503.
[9] Z. Ogumi, T. Kuroe, and Z. I. Takehara, J. Electrochem. Soc., 1985, 132, 2601.
[10] J. Cruickshank and K. Scott, J. Power Sources, 1998, 70, 40.
[11] M. Watanabe, M. Uchida, and S. Moot, J. Electroanal. Chem., 1987, 229, 396.
[12] D. X. Cao and H. S. Bergens, J. Power Sources, 2004, 134, 172.
[13] M. Gotz and H. Wendt, Electrochim. Acta, 1998, 43, 3637.
[14] J. H. Choi, K. W. Park, I. S. Park, W. H. Nam, and Y. E. Sung, Electrochim. Acta, 2004, 50, 787.
[15] K. W. Park, J. H. Choi, B. K. Kwon, S. A. Lee, Y. E. Sung, H. Y. Ha, S. A. Hong, H. Kim, and A. Weickowski, J. Phys. Chem. B, 2002, 106, 1869.
[16] Taiwan small fuel cells symposium, June 27-29 2006.
[17] M. P. Hogarth and T. R. Ralph, Platinum Metals Rev., 2002, 46, 4, 146.
[18] J. Larminie and A. Dicks, “Fuel Cell Systems Explained, Second Edition”, Wiley company, 2003.
[19] T. Freelink, W. Visscher, and J. A. R.van Veen, Surf. Sci., 1995, 335, 353.
[20] M. Watanabe and S. Motoo, J. Electroanal. Chem., 1975, 60, 267.
[21] P. Stonehart and P. N. Ross, Catal. Rev.-Sci. Eng., 1975, 12, 1.
[22] R. Liu, H. Iddir, Q. Fan, G. Hou, A. Bo, K. L. Ley, and E. S. Smotkin, J. Phys. Chem. B, 2000, 104, 2518.
[23] W. F. Lin, M. S. Zei, M. Eiswirth, G. Ertl, T. Iwasita, and W. Vielsttich, J. Phys. Chem. B, 1999, 103, 6968.
[24] G. Neri, C. Milone, A. Donato, L. Mercadante, and A. M. Visce, J. Chem Tech. Biotechnol., 1994, 60, 83.
[25] A. Honji, T. Mori, and Y. Hishinuma, J. Electrochem. Soc., 1990, 137, 2084.
[26] A. Pozio, R. F. Silva, M. D. Francesco, F. Cardellini, and L. Giorgi, Electrochimica Acta, 2002, 48, 255.
[27] H. E. V. Dam and H. V. Bekkum, J. Catal., 1991, 131, 335.
[28] S. A. Lee, K. W. Park, J. H. Choi, B. K. Kwon, and Y. E. Sung, J. Electrochem. Soc., 2002, 149, 1299.
[29] Y. Liang, H. Zhang, H. Zhong, X. Zhu, Z. Tian, D. Xu, and B. Yi, J. Catal., 2006, 238, 468.
[30] Y. Liang, H. Zhang, Z. Tian, X. Zhu, X. Wang, and B. Yi, J. Phys. Chem. B, 2006, 110, 7828.
[31] K. W. Park, J. H. Choi, S. A. Lee, C. Pak, H. Chang, and Y. E. Sung, J. Catal., 2004, 224, 236.
[32] K. W. Park, Y. E. Sung, and M. F. Toney, Electrochem. Comm., 2006, 8, 359.
[33] S. Y. Huang, C. M. Chang, and C. T. Yeh, J. Catal., 2006, 241, 400.
[34] J. W. Guo, T. S. Zhao, J. Prabhuram, R. Chen, and C. W. Wong, J. Power Sources, 2006, 156, 345.
[35] C. Xu and P. K. Shen, J. Power Sources, 2005, 142, 27.
[36] H. Daimon and Y. Kurobe, Catal. Today, 2006, 111, 182.
[37] Q. Lu, B. Yang, L. Zhuang, and J. Lu, J. Phys. Chem. B, 2005, 109, 8873.
[38] J. Prabhuram, T. S. Zhao, Z. K. Tang, R. Chen, and Z. X. Liang, J. Phys. Chem. B, 2006, 110, 5245.
[39] S. Liao, K. A. Holmes, H. Tsaprailis, and V. I. Birss, J. Am. Chem. Soc., 2006, 128, 3504.
[40] L. Mo, X. Zheng, and C.T. Yeh, Chem. Commun., 2004, 1426.
[41] M. Kang, M.W. Song, and C.H. Lee, Appl. Catal. A, 2003, 251, 142.
[42] X. Tang, B. Zhang, Y. Li, Y. Xu, Q. Xin, and W. Shen, Catal. Today, 2004, 93, 191.
[43] C. Xu and P. K. Shen, J. Power Sources, 2005, 142, 27.
[44] C. Xu and P. K. Shen, Chem. Commun., 2004, 2238.
[45] S. Y. Huang, C. M. Chang, and C. T. Yeh, J. Catal., 2006, 241, 400.
[46] J. W. Guo, T. S. Zhao, J. Prabhuram, R. Chen, and C.W. Wong, J. Power Sources, 2006, 345.
[47] K. W. Park, Y. E. Sung, and M. F. Toney, Electrochem. Comm., 2006, 8, 359.
[48] C. Xu and P. K. Shen, J. Power Sources, 2005, 142, 27.
[49] L. Chen, M. Guo, H.F Zhang, and X.D Wang, Electrochem. Acta, 2006, 52, 1191.
[50] S. Y. Huang, S. M. Chang, C.L. Lin, C. H. Chen, and C. T. Yeh, J. Phys. Chem. B, 2006, 110, 234.
[51] X. Li and I. M. Hsing, Electrochem. Acta, 2006, 52, 1358.
[52] A. H. C. Sirk, J. M. Hill, S. K. Y. Kung, and V. I. Birss, J. Phys. Chem. B, 2004, 108, 689.
[53] Y. Xu, X. Xie, J. Guo, S. Wang, Y. Wang, and V. K. Mathur, J. Power Sources, 2006, 142,132.
[54] J. W. Long, R. M. Stroud, K. E. Swider-Lyons, and D. R. Rolison, J. Phys. Chem. B, 2000, 104, 9772.
[55] K. W. Wang and C.T. Yeh, J. Colloid Interf. Sci., 2008.
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top