臺灣博碩士論文加值系統

在能源危機的時代，研究出適合的再生能源是當務之急。而再生能源中，又以太陽能電池最受到大家的矚目。太陽能電池種類繁多，若是以材料來當作區分，可以分為:矽太陽能電池、無機化合物太陽能電池、染料敏化太陽能電池、有機太陽能電池等。其中以單晶矽太陽能電池的效率最高。但是其製造的成本高，不符合經濟效益。而有機太陽能電池的優點在製作成本低，只需要用旋轉塗佈機便可以塗佈上作用層，再用加熱板加熱結晶。是屬於低溫的製程，造價低廉，加上厚度。若是用於塑膠機板上，變成可彎曲式的太陽能電池，十分有實用的價值。
此篇論文的主要研究，是以有機混合無機的太陽能電池。有機混無機的太陽能電池製作方式，是先在清洗後的ITO玻璃基板上，用水熱法的方式，來長成柱狀的ZnO，接著在旋轉塗佈上高分子P3HT、PCBM，最後蒸鍍上銀電極。此種原件在本篇論文中為標準元件。我們發現到塗佈高分子主動層之前，先用旋轉塗佈的方式塗上一層碳60的溶液，可以提高元件的整體表現。
根據分析發現，元件效率的提升最主要的原因是來自於光電流的增加。而會形成光電流增加的原因主要有兩個，分別是增加激子的分離，以及減少ZnO柱狀結構上的缺陷。根據實驗結果，電子可以更有效率的由高分子層傳遞到ZnO柱狀結構上進而更容易到達負極。依照此結論我們可以更進一步的製造出更有效率的有機太陽能電池。

At the time of energy crisis, it is urgent to find proper renewable energy. Among all the possibilities, solar cells are the most noticeable. There are many kinds of solar cells. Of all these solar cells, the crystalline based solar cells have the highest efficiency. But its production process is quite costly, lacking economical benefits. In contrast, organic solar cells have a great advantage of low cost. It only needs a spin coater to fabricate the active layer and then annealed with a hotplate. With its low cost and thin thickness, it would be practical to use them on plastic board to make flexible solar cells.
This thesis is mainly focused on the research of inorganic/organic hybrid solar
cells. The inorganic/organic hybrid solar cells are made from ZnO rods and polymer
P3HT/PCBM. After cleaning the ITO glass, ZnO rods were fabricated by the hydrothermal method, and then P3HT/PCBM was spin coated on ZnO nanorods. Finally, Ag contact was evaporated for the measurement of photocurrent. We discover that a thin layer deposited by spin coated C60 solution before the fabrication of P3HT/PCBM layer can greatly improve the performance of solar cells. The main reasons for the increased efficiency of solar cells can be attributed to the enhanced exciton separation as well as the reduction of defect states. As a result, charges can transfer from polymer blend to ZnO-nanorod more effectively and subsequently travel to electrodes leading to the improved performance in the photovoltaic devices.

1.Introduction.............................................1
Reference..................................................4
2.Theoretical Background...................................5
2.1 The principle of solar cell...........................5
2.1.1 Solar Spectrum.......................................5
2.1.2 Photovoltaic effect..................................7
2.1.3 Open Circuit Voltage.................................8
2.1.4 Short Circuit Current...............................10
2.1.5 Filling Factor＆Efficiency.........................10
2.1.6 Device Analysis.....................................11
2.2 Organic semiconductor................................12
2.3 Organic solar cells structures.......................14
2.3.1 Bilayer heterojunction..............................14
2.3.2 Bulk heterojunction.................................15
Reference.................................................17
3. Equipments and Experimental Details...................19
3.1 Equipment.............................................19
3.1.1 Scanning electron microscopy.......................19
3.1.2 Photoluminescence..................................21
3.1.3 Time-resolved photoluminescence....................23
3.1.4 Thermal evaporation................................25
3.1.5 Solar simulator....................................26
3.2 Brief description of the studied materials............27
3.2.1 ZnO nanowire.......................................27
3.2.2 Organic materials..................................29
Reference.................................................31
4. The effect of C60 on ZnO nanorods in inorganic-organic hybrid photovoltaics......................................32
4.1 Introduction..........................................32
4.2 Experiment............................................35
4.3 Results and discussions...............................37
4.4 Summary...............................................42
Reference.................................................47
5.Conclusion..............................................49

1. Wendy U. Huynh, Janke J.Dittmer,A.Alivisatos, Science Vol 295 29 March (2002).
2. F. Padinger, R.S. Rittberger, and N.S. Sariciftci, Adv. Funct. Mater 13, 1(2003).
3. C.D. Dimitrakopoulos and D.J.Mascaro, IBM J.Res.Dev.45, 11(2001).
4. R. H. Friend, G. J. Denton, J. J. M. Halls, N. T. Harrison, A. B. Holmes, A. Kohler, A. Lux, S. C. Moratti, K. Pichler, N. Tessler, K. Towns, and H. F. Wittmann, Solid State Commun. 102, 249 (1997).
5. T. J. Savenije, J. M. Warman, and A. Goossens, Chem. Phys. Lett. 287, 148 (1998).
6. K. M. Coakley and M. D. McGehee, Appl. Phys. Lett. 83, 3380 (2003).
7. P. Ravirajan, S. A. Haque, J. R. Durrant, D. D. C. Bradley, and J. Nelson, Adv. Funct. Mater. 15, 609 (2005).
8. Q. Wei, K. Hirota, K. Tajima, and K. Hashimoto, Chem. Mater. 18, 5080 (2006).
9. P. Ravirajan, A. M. Peiró, M. K. Nazeeruddin, M. Graetzel, D. D. C. Bradley, J. R. Durrant, and J. Nelson, J. Phys. Chem. B 110, 7635 (2006).
10. D. C. Olson, J. Piris, R. T. Collins, S. E. Shaheen, and D. S. Ginley, Thin Solid Films 496, 26 (2006).
11. Y. Y. Lin, C. W. Chen, T. H. Chu, W. F. Su, C. C. Lin, C. H. Ku, J. J. Wu, and C. H. Chen, J. Mater. Chem. 17, 4571 (2007).

1. http://www.energyharvestingjournal.com/glossary/am-designation_297.asp?sessionid=1
2. J.Rostalski, D.Meissner, Solar Energy Materials and Solar cells, 61, 87 (2000)
3. www.newport.com/Introduction-to-solar-Radiation/411919/1033/catalog.aspx
4. http://www.techonline.com/tigforums/thread.jspa%3fthreadID=4007
5. G.A.Chamberlain: Organic solar cell: A review. Solar Cells 8, 47 (1983)
6. D.Wohrle and D.Meissner: Organic solar cells. Adv. Mater. 3, 129 (1991)
7. H.Hooppe et al.: Organic solar cells : An overview. J.Mater.Res. Vol.19, No.7, Jul (2004)
8. http://www.uni-potsdam.de/u/physik/fprakti/ANLEIW4.pdf
9. T.L.Benanti, D.Venkataraman, Photosynthesis Research, 87 (2006)
10. P.Peumans, A.Yakimov, and S.R.Forrest: Small molecular weight organic thin-film photodetectors and solar cells. J.Appl.Phys.93,3693 (2003)
11. L.A.A.Pettersson, L.S.Roman, and O.Inganas: Modeling photocurrent action spectra of photovoltaic devices based on organic thin films. J.Appl.Phys.86,487 (1999)
12. C.W.Tang: Two-layer organic photovoltaic cell. Appl. Phys.Lett.48,183 (1986)
13. J.Rostalski and D.Meissner: Photocurrent spectroscopy for the investigation of charge carrier generation and transport mechanisms in organic p/n-junction solar cells. Sol.Energy Mater.sol.Cells 63,37 (2000)
14. N.S.Sariciftci, L.smilowitz, A.J.Heeger, and F.Wudl: Photoinduced electron transfer from a conducting polymer to buck-minsterfullerene. Science 258,1474(1992)
15. M. Hiramoto, Y. Kishigami, and M.Yokoyama: Doping effect on the two-layer organic solar cell. Chem.Lett.19,119 (1990)
16. J.J.M.Halls, K.Pichler, R.H. Friend, S.C.Moratti, and A.B. Holmes:Exciton diffusion and dissociation in a poly(p-phenylenevinylene)/C60 heterojunction photovoltaic cell. Appl. Phys. Lett. 68, 3120 (1996)
17. J.J.M.Halls and R.H.Friend: The photovoltaic effect in a poly (p-phenylenevinylene)/perylene heterojunction.Synth.Met.85,1307 (1997)
18. N.S.Sariciftci, D.Braun, C.Zhang, V.I.Srdanov, A.J. Heeger, G.Stucky, and F.Wudl: Semiconducting polymerbuckminsterfullerene heterojunctions: Diodes, photodiodes, and photovoltaic cells.Appl.Phys.Lett.62,585 (1993)
19. L.S.Roman, W.Mammo, L.A.A.Petterson, M.R.Anderson, and O.Inganas: High quantum efficiency polythiophene/C60 photodiodes.Adv.Mater.10,774 (1998)

1. G.I. Goldstein, D.E. Newbury, P. Echlin, D.C. Joy, C. Fiori, and E. Lifshin, Scanning electron microscopy and X-ray microanalysis , Plenum Press, New York and London (1981).
2. Jason B. Baxter, Eray S. Aydil , Journal of Crystal Growth 274(2005)407-411
3. N.E. Hsu, W.K. Hung, and Y.F. Chen, J. Appl. Phys. 96 , 4671 (2004)

1. R. H. Friend, G. J. Denton, J. J. M. Halls, N. T. Harrison, A. B. Holmes, A. Kohler, A. Lux, S. C. Moratti, K. Pichler, N. Tessler, K. Towns, and H. F. Wittmann, Solid State Commun. 102, 249 (1997).
2. T. J. Savenije, J. M. Warman, and A. Goossens, Chem. Phys. Lett. 287, 148 (1998).
3. K. M. Coakley and M. D. McGehee, Appl. Phys. Lett. 83, 3380 (2003).
4. P. Ravirajan, S. A. Haque, J. R. Durrant, D. D. C. Bradley, and J. Nelson, Adv. Funct. Mater. 15, 609 (2005).
5. Q. Wei, K. Hirota, K. Tajima, and K. Hashimoto, Chem. Mater. 18, 5080 (2006).
6. P. Ravirajan, A. M. Peiró, M. K. Nazeeruddin, M. Graetzel, D. D. C. Bradley, J. R. Durrant, and J. Nelson, J. Phys. Chem. B 110, 7635 (2006).
7. D. C. Olson, J. Piris, R. T. Collins, S. E. Shaheen, and D. S. Ginley, Thin Solid Films 496, 26 (2006).
8. Y. Y. Lin, C. W. Chen, T. H. Chu, W. F. Su, C. C. Lin, C. H. Ku, J. J. Wu, and C. H. Chen, J. Mater. Chem. 17, 4571 (2007).
9. J. S. Huang, C. Y. Chou, M. Y. Liu, K. H. Tsai, W. H. Lin, and C. F. Lin, Org. Electron. 10, 1060 (2009).
10. C. Y. Kuo and C. Gau, Appl. Phys. Lett. 95, 053302 (2009).
11. K. Takanezawa, K. Hirota, Q. Wei, K. Tajima, and K. Hashimoto, J. Phys. Chem. C 111, 7218 (2007).
12. P. Ravirajan, A. M. Peiro, M. K. Nazeeruddin, M. Graetzel, D. D. C. Bradley, J. R. Durrant, and J. Nelson, J. Phys. Chem. B 110, 7635 (2006).
13. A. M. Peiro, P. Ravirajan, K. Govender, D. S. Boyle, P. O’Brien, D. D. C. Bradley, J. Nelson, and J. R. Durrant, J. Mater. Chem. 16, 2088 (2006).
14. M. A. Green, K. Emery, Y. Hishikawa, W. Warta, Properties in Photovoltaics: Research and Applications, 16, 16 (2008).
15. M.Ohyama, H. Kozuka, T. Yoko, Thin Solid Films, 306, 78 (1997).
16. L. Vayssieres, Adv. Mater, 15, 464 (2003).
17. J. S. Huang, C. Y. Chou, and C. F. Lin, Sol. Energy Mater. Sol. Cells 94, 182 (2010).
18. H. Z. Yu and J. B. Peng, Org. Electron. 9,1002 (2008).