研究生: |
湯杜翔 Du-Hsiang Tang |
---|---|
論文名稱: |
奈米柱應用於燃料電池電極之技術開發 Development of nanopillar arrays for fabricating the electrodes of a fuel cell |
指導教授: |
程金保
Cheng, Chin-Pao 楊啟榮 Yang, Chii-Rong |
學位類別: |
碩士 Master |
系所名稱: |
機電工程學系 Department of Mechatronic Engineering |
論文出版年: | 2006 |
畢業學年度: | 94 |
語文別: | 中文 |
論文頁數: | 125 |
中文關鍵詞: | 奈米柱 、光輔助電化學蝕刻 、精密電鑄 、直接甲醇燃料電池電極 |
英文關鍵詞: | nanopillar, photo-assisted electrochemical etching, electroforming, direct methanol fuel cell |
論文種類: | 學術論文 |
相關次數: | 點閱:209 下載:9 |
分享至: |
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
摘 要
直接甲醇燃料電池(DMFC)是未來令人期待的科技,目前的發展方向在於3C產品的應用(如筆記型電腦、手機)、攜帶式電源供應器等。然而,目前發展DMFC仍有幾項瓶頸仍待克服,例如提升電極觸媒催化效能、減少甲醇不必要的穿透現象,這些負面影響均使其輸出功率依舊無法滿足實際應用的需求。由文獻可知,為了製作高低不平電極,以提升直接甲醇燃料電池效率,皆需使用感應耦合電漿離子蝕刻技術。然而,由於這些設備高價格之缺點,使得學術界與中小型企業難以投入相關的研究。根據上述,本研究將結合「自組裝奈米球微影」、「光輔助電化學蝕刻」、「精密電鑄」技術,預期將可成為低成本,並且用以製作出完美且具大規模排列之奈米柱狀陣列結構,藉由電極接觸表面積之大量增加,來提高反應性,以應用於直接甲醇燃料電池電極之開發。
實驗的結果証實結合薄光阻格狀結構製作及震盪塗佈法的方式,可將奈米球規則地排列於矽基板上,以得到大面積且趨近完美排列的奈米球陣列。而在光輔助電化學蝕刻的實驗中,當使用1 V的蝕刻電壓與HF濃度2.5 wt%的蝕刻液,蝕刻30分鐘後,能夠產生高度約為7.4 m,直徑約為90 nm,而孔洞的深寬比可達到67:1之高深寬比孔洞。並且証實加大蝕刻電壓機制使蝕刻孔洞擴孔及適當RIE蝕刻時間,即可製作出柱體高度約為1.56 µm,直徑約為250 nm~300 nm,因此柱體的深寬比可達6.2:1~5.2之奈米柱狀陣列。目前直接甲醇燃料電池電極測試性能後,結果顯示平板電極其開路電壓、極限電流密度、最大功率密度分別為105 mV、0.319 mA/cm2、0.0093 mW/cm2,柱狀電極其最大開路電壓、極限電流密度、最大功率密度分別為280 mV、1.044 mA/cm2、0.0584 mW/cm2,本實驗發現柱狀電極所製作燃料電池之最大功率密度優於平板電極6.3倍,顯示蝕刻電壓增加所製作之柱狀電極結構可提升觸媒與燃料接觸之表面積,使其性能也隨之提升。
關鍵字:奈米柱,光輔助電化學蝕刻,精密電鑄,直接甲醇燃料電池電極。
Abstract
A direct methanol fuel cell (DMFC) is the much-anticipated science and technology in the future, the present developing direction such as application of 3C products and portable power supplying device. However, the DMFC still has the following drawbacks to overcome, for example improve the catalyst efficiency of electrodes and reduce the methanol crossover phenomenon, it makes its output power is still unable to meet practical applications. According to the past approach, in order to make the rugged electrodes, it has to use the inductively coupled plasma reactive ion etching (ICP-RIE) technique, but these equipments are expensive. The research will integrate nanosphere lithography, photo-assisted electrochemical etching (PAECE) and electroforming techniques for fabricating perfect and high regular arrangement of the nanopillars array structure. If all techniques that we adopt can be integrated successfully, low cost, fabricating perfect and high regular arrangement of the nanopillars array can be realized. In addition, we can fabricate the electrodes in the direct methanol fuel cell by means of these techniques.
Experiment results show that self-assembly nanosphere lithography, it can be used to define nano-pattern array by integrating thin photoresist and vibration method. The novel coating method of nanosphere can arrange nanosphere regularly. Nanohole can be easily obtained in PAECE process, which dimensions of width and height is 90 nm and 7.4 µm (aspect ratio, 67:1). We have finished the fabrication process of nanopillar array by using PAECE technique. Nanopillar array can be regularly arranged, which dimensions of width and height is 250 nm~300 nm and 1.56 µm (aspect ratio, 6.2:1~5.2.:1). The nanopillar electrode (9.3 mA/cm2) showed 3 times larger current density than that from planar electrode (3.1 mA/cm2) at electrode potential of 1V. We found the nanopillar electrode DMFC (58.4 µW/cm2) showed maximum 6.3 times higher power density than the planar electrode DMFC (9.3 µW/cm2) in fuel cell test.
Keywords: nanopillar, photo-assisted electrochemical etching, electroforming, direct methanol fuel cell.
參考文獻
1. 楊啟榮 等人, "微機電系統技術與應用", 精密儀器發展中心, 第四章, pp. 141-142 (2003).
2. 楊啟榮, "微機電系統技術導論", 國立台灣師範大學上課講義 (2001).
3. W. Barthlott, and C. Neinhuis, "Purity of the sacred lotus, or escape from contamination in biological surfaces", Planta, Vol. 202, pp. 1-8 (1997).
4. G. Pirio, P. Legagneux, D. Pribat, K. B. K. Teo, M. Chhowalla, G. A. J. Amaratunga, and W. I. Milne, "Fabrication and electrical characteristics of carbon nanotube field emission microcathodes with an integrated gate electrode", Nanotechnology, Vol. 13, pp. 1-4 (2002).
5. H. Ohji, S. Izuo, P.J. French, and K. Tsutsumi, "Pillar structures with a sub-micron space fabricated by macroporous-based micromachining", Sensors and Actuators, A 97-98, pp. 744-748 (2002).
6. 賴秋助 等人, "微小型直接甲醇燃料電池系統設計", 工業材料雜誌, 193, pp. 120-125 (2003).
7. http://www.nec.co.jp/press/en/0306/3002.html
8. 高志勇 等人, "直接甲醇燃料電池製程技術發展現況", 工業材料雜誌, 193, pp. 111-119 (2003).
9. W. Y. Sim, G. Y. Kim, and S. S. Yang, "Fabrication of micro power source (MPS) using a micro direct methanol fuel cell (DMFC) for the medical application", Journal of Microelectromechanical Systems, pp. 341-344 (2001).
10. A. Geiger, E. Lehmann, P. Vontobel, and G.G. Scherer, "Direct methanol fuel cell-in situ investigation of carbon dioxide patterns in anode flow fields by neutron radiography", Journal of Applied Electrochemistry, Vol. 29, pp. 86-87 (1999).
11. A. G. Nassiopoulos, S. Grigoropoulos, E. Gogolides, and D. Papadimitriou, "Visible luminescence from one- and two-dimensional silicon structures produced by conventional lithographic and reactive ion etching techniques", Applied Physics Letters, Vol. 66, number 9, pp. 1114-1116 (1995).
12. H. G. Teo, M. B. Yu, J. Singh, N. Ranga, J. Li, W. C. Yew, and A. Q. Liu, "Realization of high aspect ratio nanopillar type photonic crystal by deep reactive ion etching", 2004 Digest of the LEOS Summer Topical Meetings, pp. 83-84 (2004).
13. N. Kaji, Y. Tezuka, Y. Takamura, M. Ueda, T. Nishimoto, H. Nakanishi, Y. Horiike, and Y. Baba, "Separation of long DNA molecules by quartz nanopillar chips under a direct current electric field", Analytical Chemistry, Vol. 76, pp. 15-22 (2004).
14. T. Tada, A. Hamoudi, T. Kanayama, and K. Koga, "Spontaneous production of 10-nm Si structures by plasma etching using self-formed masks", Applied Physics Letters, Vol. 70, pp. 2538-2540 (1997).
15. P. A. Lewis, H. Ahmed, and T. Sato, "Silicon nanopillars formed with gold colloidal particle masking", Journal of Vacuum Science and Technology B, Vol. 16, number 6, pp. 2938-2941 (1998).
16. Y. K. Hong, J. H. Bahng, G. Lee, H. Kim, W. Kim, S. Lee, J. Y. Koo, J. I. Park, W. R. Lee, and J. Cheon, "Facile fabrication of 2-dimensional arrays of sub-10 nm single crystalline Si nanopillars using nanoparticle masks", Chemical Communications, pp. 3034-3035 (2003).
17. C. W. Kuo, J. Y. Shiu, P. Chen, and G. A. Somorjai, "Fabrication of size tunable large-area periodic silicon nanopillar arrays with sub-10-nm resolution", Journal of Physical Chemistry B, Vol. 107, number 37, pp. 9950-9953 (2003).
18. P. Yang, "Controlled growth of ZnO nanowires and their optical properties", Advanced Functional Materials, Vol. 12, number 5, pp. 323-331 (2002).
19. J. L. Taraci, J. W. Dailey, T. Clement, D. J. Smith, J. Drucker, and S. T. Picraux, "Nanopillar growth mode by vapor-liquid-solid epitaxy", Applied Physics Letters, Vol. 84, number 26, pp. 5302-5304 (2004).
20. M. Jaffe, "High performance synthetic fibers for composites", Repot of the Committee on Engineering and Technical Systems, pp. 89 (1992).
21. J. Liang, H. Chik, and J. Xu, "Nonlithographic fabrication of lateral superlattices for nanometric electromagnetic-optic applications", Selected Topics in Quantum Electronics, Vol. 8, number 5, pp. 998-1008 (2002).
22. K. Kuwabara, M. Ogino, S. Motowaki, and A. Miyauchi, "Fluorescence measurements of nanopillars fabricated by high-aspect-ratio nanoprint technology", Microelectronic Engineering, Vol. 73-74, pp. 752-756 (2004).
23. P. Silverman, "Manufacturing with EUV", (2000).
24. T. Brunner, "Pushing the limits of lithography for IC production", Electron Devices Meeting, pp. 1.2.1-1.2.5 (1997).
25. L. R. Harriott, "Limits of lithography", proceedings of the IEEE, Vol. 89, number 3, pp. 366-374 (2001).
26. S. Tedesco, "Next generation lithography: the challenges of nano lithography", Minatec Innovative Centre, (2003).
27. T. Matsuo, M. Endo, S. Kishimulra, A. Misaka, M. Sasago, "Lithography solution for 65-nm node system LSIs", 2002 VLSI Technology Digest of Technical Papers, pp. 196-197 (2002).
28. A. R. Reinberg, "Etching and lithography running neck and neck", Circuits and Devices Magazine, Vol. 9, number 1, pp. 24-29 (1993).
29. A. Uhir, "Electrolytic shapping of germanium and silicon", Bell System Technical Journal, Vol. 35, pp. 333-341 (1956).
30. Y. Watanabe, Y. Arita, T. Yokoyama, and Y. Igarashi, "Formation and properties of porous silicon and its application", Journal of the Electrochemical society, Vol. 122, pp. 1351-1358 (1975).
31. C. Pickering, M. J. J. Beale, D. J. Robbins, P. J. Pearson, and R. Greef, "Optical studies of the structure of porous films formed in p-type degenerate and non-degenerate silicon", Journal of Physics C: Solid State Physics, Vol. 17, pp. 6535-6552 (1984).
32. V. Lehmann, U. Gosele, "Porous silicon formation a quantum wire effect", Applied Physics Letter, Vol. 58, number 8, pp. 856-858 (1991).
33. A. Richter, "Current-induced light-emission from a porous silicon device", IEEE Electron Device Letter, Vol. 12, number 12, pp. 691-692 (1991).
34. V. Lehmann, and U. Grüning, "The limits of macropore array fabrication", Thin Solid Films, Vol. 297, pp. 13-17 (1997).
35. V. Lehmann, "The physics of macropore formation in low-doped n-type silicon", Journal of the Electrochemical Society, Vol. 140, pp. 2836-2843 (1993).
36. M. D. B. Charlton, H. W. Lau, and G. J. Parker, "High aspect ratio photo-assisted electro-chemical etching of silicon and its application for the fabrication of quantum wires and photonic band structures", Microengineering Applications in Optoelectronics, pp. 1-9 (1996).
37. V. Lehmann, "Porous silicon formation and other photoelectrochemical effects at silicon electrodes anodized in hydrofluoric acid", Applied Surface Science, Vol. 106, pp. 402-405 (1996).
38. S. Izuo, H. Ohji, and P. J. French, "A novel electrochemical etching technique for n-type silicon", Sensors and Actuators A, Vol. 97-98, pp. 720-724 (2002).
39. G. Barillaro, A. Nannini, and M. Piotto, "Electrochemical etching in HF solution for silicon micromachining", Sensors and Actuators A, Vol. 102, pp. 195-201 (2002).
40. G. D. Arrigo, S. Coffa, and C. Spinella, "Advanced micromachining processes for micro-opto-electromechanical components and devices", Sensors and Actuators A, Vol. 99, pp. 112-118 (2002).
41. H. Ohji, P. J. Trimp, and P. J. French, "Fabrication of free standing structure using single step electrochemical etching in hydrofluoric acid", Sensors and Actuators, Vol. 73, pp. 95-100 (1999).
42. R. L. Smith, and S. D. Collins, "Porous silicon formation mechanisms", Journal of Applied Physics. Vol. 71, number 8, pp. R1-R22 (1992).
43. V. Lehmann, "Porous silicon-a new material for MEMS", Proceedings of 1996 MEMS, pp. 1-6 (1996).
44. 楊啟榮等人, "微機電系統技術與應用", 精密儀器發展中心, 第四章, pp. 225-246 (2003).
45. K. Wozniak, D. Johansson, M. Bring, and P. Enoksson, "A micro direct methanol fuel cell demonstrator", Journal of Micromechanics and Microengineering, Vol. 14, pp. S59-S63 (2004).
46. K. G. Stanley, Q. M. Jonathan, and W. T. Vanderhoek, "Fabrication of a micromashined micro direct methanol fuel cell", Proceedings of the 2002 IEEE Canadian Conference on Electrical & Computer Engineering, pp. 450-454 (2002).
47. G. Q. Lu, C. Y. Wang, T. J. Yen, and X. Zhang, "Development and characterization of a silicon-based micro direct methanol fuel cell", Electrochimica Acta, Vol. 49, pp. 821-828 (2004).
48. Y. H. Seo, and Y. H. Cho, "A miniature direct methanol fuel cell using platinum sputtered microcolumn electrodes with limtted amount of fuel", Journal of Microelectromechanical Systems, pp. 375-378 (2003).
49. Y. Yamazaki, "Application of MEMS technology to micro fuel cells", Electrochimica Acta, Vol. 50, pp. 663-666 (2004).
50. S. Onoe, H. Tanaka, K. Hoshino, K. Matsumoto, and I. Shimoyama, " Miniature fuel cell with conductive silicon electrodes", The 13th International Conference on Solid-State Sensors, Actuators and Microsystems, pp. 1296-1299 (2003).
51. 呂俊逸, "質子交換膜燃料電池研究─MEA的製造和性能分析", 中山大學機械工程研究所碩士論文, pp. 31-32 (2000).
52. 黃秋萍 等人, "直接甲醇燃料電池的核心膜電極組(MEA)", 工業材料雜誌, 202, pp.141-150 (2003).
53. "Material safety data sheet", Polysciences Inc.
54. C. S. Solanki, R. R. Bilyalov, J. Poortmans, J. P. Celis, J. Niji, and R. Mertens, “Self-standing porous silicon films by one-step anodizing”, Journal of the Electrochemical Society, Vol. 151, pp.307-314 (2004).
55. J. Yeom, G. Z. Mozsgai, B. R. Flachsbart, E. R. Choban, and A. Asthana, "Microfabrication and characterization of a silicon-based millimeter scale, PEM fuel cell operating with hydrogen, methanol, or formic acid", Sensors and Actuators B, Vol. 107, pp. 882-891 (2005).