藉著電紡絲的技術製備的二氧化鈦奈米纖維被用作為產生光補獲效應的基材，並同時作為以對聚噻吩為主動層的太陽能電池中傳導電子的材料。電紡絲中，光散射的效應會隨著絲直徑不同而有不同的散射波長，而光行經的路程也會隨著絲整體沉積的量增加而有顯著的提升。在組裝好的太陽能電池中，針對幾個部分做探討，一個是對電紡絲做熱壓的處理，對聚噻吩/電紡絲的比例，以及不同直徑的散射峰對於電池整體表現的影響等等。當電紡絲的直徑在290nm時，其散射峰的位置正好與對聚噻吩的吸收峰產生重疊，這樣的直徑造成的散射峰較其它四種直徑對於電池在電流密度及效率方面都有更好的提升。在增加整體電紡絲沉積的量後，電流密度的提升以及對整體效率的增進，都證明了在對聚噻吩/二氧化鈦奈米纖維製備的異質接面太能陽電池的研究中，光補獲效應造成的影響。

Randomly deposited titania nanofibers from the polymer-assisted electrospinning fabrications were utilized as the light propagation matrix and the electron transporter in the poly(3-hexyl thiophene) (P3HT)/TiO2 heterojunction solar cells. Taking the advantages of light scattering effects occurred within the titania nanofiber scaffolds, the light path lengths of the incident irradiation were significantly increased as functions of fiber diameters and fiber deposition thicknesses. Assembles of the P3HT/TiO2 heterojunction photovoltaic devices were first investigated in terms of the extra fiber compression, the P3HT/TiO2 ratios, the preferred scattering bands, and more. Photovoltaic outcomes were then carefully examined and analyzed. For the light scattering and propagation effect, it was found that the titania nanofiber with the average diameter of 290nm had the preferred scattering band mostly overlapped with the P3HT absorption wavelength. As a result, this particular sample revealed the best performance in comparison with other devices with different titania fiber diameters. Moreover, the thickening of titania nanofiber deposition layers was incorporated with the increase of energy conversion. Experimental results showed that the current densities and the fill factors were both linearly increased with the cell thicknesses, suggesting the energy accumulation from the light scattering effects. These observations indicated the light propagation and the improvement of energy conversion efficiencies were successfully demonstrated in the solid-state heterojunction solar cells constructed by electrospun titania nanofibers and conducting polymers.

1. Oregan, B.; Gratzel, M., A Low-Cost, High-efficiency Solar-Cell Based on Dye-Sensitized Colloidal TiO2 Fillms. Nature 1991, 353 (6346), 737-740.
2. Zhang, W.; Zhu, R.; Liu, X. Z.; Liu, B.; Ramakrishna, S., Facile construction of nanofibrous ZnO photoelectrode for dye-sensitized solar cell applications. Applied Physics Letters 2009, 95 (4).
3. Greene, L. E.; Law, M.; Yuhas, B. D.; Yang, P. D., ZnO-TiO2 core-shell nanorod/P3HT solar cells. Journal of Physical Chemistry C 2007, 111 (50), 18451-18456.
4. Law, M.; Greene, L. E.; Radenovic, A.; Kuykendall, T.; Liphardt, J.; Yang, P. D., ZnO-Al2O3 and ZnO-TiO2 core-shell nanowire dye-sensitized solar cells. Journal of Physical Chemistry B 2006, 110 (45), 22652-22663.
5. Her, H. J.; Kim, J. M.; Kang, C. J.; Kim, Y. S., Hybrid photovoltaic cell with well-ordered nanoporous titania-P3HT by nanoimprinting lithography. Journal of Physics and Chemistry of Solids 2008, 69 (5-6), 1301-1304.
6. Yu, B. Y.; Tsai, A.; Tsai, S. P.; Wong, K. T.; Yang, Y.; Chu, C. W.; Shyue, J. J., Efficient inverted solar cells using TiO2 nanotube arrays. Nanotechnology 2008, 19 (25).
7. Charoensirithavorn, P.; Ogomi, Y.; Sagawa, T.; Hayase, S.; Yoshikawa, S., Effect of Heat-Treatment on Electron Transport Process in TiO2 Nanotube Arrays Prepared Through Liquid Phase Deposition for Dye-Sensitized Solar Cells. Journal of the Electrochemical Society 2009, 156 (11), H803-H807.
8. Chuangchote, S.; Sagawa, T.; Yoshikawa, S., Efficient dye-sensitized solar cells using electrospun TiO2 nanofibers as a light harvesting layer. Applied Physics Letters 2008, 93 (3).
9. Lu, X. F.; Wang, C.; Wei, Y., One-Dimensional Composite Nanomaterials: Synthesis by Electrospinning and Their Applications. Small 2009, 5 (21), 2349-2370.
10. King, R. R.; Law, D. C.; Edmondson, K. M.; Fetzer, C. M.; Kinsey, G. S.; Yoon, H.; Sherif, R. A.; Karam, N. H., 40% efficient metamorphic GaInP/GaInAs/Ge multijunction solar cells. Applied Physics Letters 2007, 90 (18).
11. Luque, A.; Marti, A., Increasing the efficiency of ideal solar cells by photon induced transitions at intermediate levels. Physical Review Letters 1997, 78 (26), 5014-5017.
12. Ley, M.; Boudaden, J.; Kuznicki, Z. T., Thermodynamic efficiency of an intermediate band photovoltaic cell with low threshold Auger generation. Journal of Applied Physics 2005, 98 (4).
13. Rosenwaks, Y.; Thacker, B. R.; Ahrenkiel, R. K.; Nozik, A. J.; Yavneh, I., Photogenerated Carrier Dynamics Under The Influence of Electric-Fields in III-V Semiconductorss. Physical Review B 1994, 50 (3), 1746-1754.
14. Sevik, C.; Bulutay, C., Auger recombination and carrier multiplication in embedded silicon and germanium nanocrystals. Physical Review B 2008, 77 (12), 125414.
15. Yoffa, E. J., Screening of hot-carrier relaxation in highly photoexcited semiconductors. Physical Review B 1981, 23 (4), 1909.
16. Shank, C. V.; Fork, R. L.; Leheny, R. F.; Shah, J., Dynamics of Photoexcited GaAs Band-Edge Absorption with Subpicosecond Resolution. Physical Review Letters 1979, 42 (2), 112.
17. Carp, O.; Huisman, C. L.; Reller, A., Photoinduced reactivity of titanium dioxide. Progress in Solid State Chemistry 2004, 32 (1-2), 33.
18. Shangguan, W.; Yoshida, A.; Chen, M., Physicochemical properties and photocatalytic hydrogen evolution of TiO2 films prepared by sol-gel processes. Solar Energy Materials and Solar Cells 2003, 80 (4), 433.
19. Ovenstone, J.; Yanagisawa, K., Effect of Hydrothermal Treatment of Amorphous Titania on the Phase Change from Anatase to Rutile during Calcination. Chemistry of Materials 1999, 11 (10), 2770-2774.
20. Tzung-Ying, S., Electrospun Titanium Dioxide Nanofibers for Hydrogen Production by UV-Induced Water Splitting. 2007.
21. Li, F. B.; Li, X. Z., Photocatalytic properties of gold/gold ion-modified titanium dioxide for wastewater treatment. Applied Catalysis a-General 2002, 228 (1-2), 15-27.
22. Feng, B.; Weng, J.; Yang, B. C.; Qu, S. X.; Zhang, X. D., Characterization of surface oxide films on titanium and adhesion of osteoblast. Biomaterials 2003, 24 (25), 4663-4670.
23. Yoko, T.; Hu, L.; Kozuka, H.; Sakka, S., Photoelectrochemical properties of TiO2 coating films prepared using different solvents by the sol-gel method. Thin Solid Films 1996, 283 (1-2), 188.
24. Adam, D., A fine set of threads. Nature 2001, 411 (6835), 236-236.
25. Dzenis, Y., MATERIAL SCIENCE: Spinning Continuous Fibers for Nanotechnology. Science 2004, 304 (5679), 1917-1919.
26. Huang, Z.-M.; Zhang, Y. Z.; Kotaki, M.; Ramakrishna, S., A review on polymer nanofibers by electrospinning and their applications in nanocomposites. Composites Science and Technology 2003, 63 (15), 2223.
27. Formhals, A., Process and Apparatus for Preparing Artificial Threads. US patent 1934, 1, 975,504.
28. Taylor, G., Electrically Driven Jets. Proceedings of Royal Society of London A:
Mathematical and Physical Sciences 1969, 313, 453.
29. MacIas, M.; Chacko, A.; Ferraris, J. P.; Balkus Jr, K. J., Electrospun mesoporous metal oxide fibers. Microporous and Mesoporous Materials 2005, 86 (1-3), 1-13.
30. Li, D.; Wang, Y.; Xia, Y., Electrospinning of Polymeric and Ceramic Nanofibers as Uniaxially Aligned Arrays. Nano Lett. 2003, 3 (8), 1167-1171.
31. Li, D.; Xia, Y., Fabrication of Titania Nanofibers by Electrospinning. Nano Lett. 2003, 3 (4), 555-560.
32. Larsen, G.; Velarde-Ortiz, R.; Minchow, K.; Barrero, A.; Loscertales, I. G., A Method for Making Inorganic and Hybrid (Organic/Inorganic) Fibers and Vesicles with Diameters in the Submicrometer and Micrometer Range via Sol?el Chemistry and Electrically Forced Liquid Jets. Journal of the American Chemical Society 2003, 125 (5), 1154-1155.
33. Kataphinan, W.; Teye-Mensah, R.; Evans, E. A.; Ramsier, R. D.; Reneker, D. H.; Smith, D. J. In High-temperature fiber matrices: Electrospinning and rare-earth modification, Papers from the 49th International Symposium of the American Vacuum Society, Denver, Colorado (USA), AVS: Denver, Colorado (USA), 2003; pp 1574-1578.
34. Sung-Seen, C.; Seung Goo, L.; Seung Soon, I.; Seong Hun, K.; Joo, Y. L., Silica nanofibers from electrospinning/sol-gel process. Journal of Materials Science Letters 2003, 22 (12), 891-893.
35. Wang, Y.; Furlan, R.; Ramos, I.; Santiago-Aviles, J. J., Synthesis and characterization of micro/nanoscopic Pb(Zr[sub 0.52]Ti[sub 0.48])O[sub 3] fibers by electrospinning. Applied Physics A: Materials Science & Processing 2004, 78 (7), 1043-1047.
36. Zhang, G.; Kataphinan, W.; Teye-Mensah, R.; Katta, P.; Khatri, L.; Evans, E. A.; Chase, G. G.; Ramsier, R. D.; Reneker, D. H., Electrospun nanofibers for potential space-based applications. Materials Science and Engineering B 2005, 116 (3), 353-358.
37. Mie, G., Contributions to the Optics of Turbid Media, Particularly of Colloidal Metal Solutions. Annals of Physics 1908, 25 (3), 377-445.
38. Ghannam, M. Y.; Abouelsaood, A. A.; Nijs, J. F., A semiquantitative model of a porous silicon layer used as a light diffuser in a thin film solar cell. Solar Energy Materials and Solar Cells 2000, 60 (2), 105-125.
39. Abouelsaood, A. A.; Ghannam, M. Y.; Stalmans, L.; Poortmans, J.; Nijs, J. F., Experimental testing of a random medium optical model of porous silicon for photovoltaic applications. Progress in Photovoltaics: Research and Applications 2001, 9 (1), 15-26.
40. Seel, H.; Brendel, R., Optical absorption in crystalline Si films containing spherical voids for internal light scattering. Thin Solid Films 2004, 451-452, 608-611.
41. Zettner, J.; Thoenissen, M.; Th, H.; Brendel, R.; Schulz, M., Novel porous silicon backside light reflector for thin silicon solar cells. Progress in Photovoltaics: Research and Applications 1998, 6 (6), 423-432.
42. Rinke, T. J. B., R. B.; Bruggemann, R.; Werner, J. H., Ultrathin quasi-monocrystalline silicon films for electronic devices. . Diffusion and Defect Data--Solid State Data, Pt. B: Solid State Phenomena 1999, 67-68, 229-234.
43. Bilyalov, R.; Solanki, C. S.; Poortmans, J.; Richard, O.; Bender, H.; Kummer, M.; von K鄚el, H., Crystalline silicon thin films with porous Si backside reflector (abstract only). Solar Energy Materials and Solar Cells 2002, 72 (1-4), 221-221.
44. Nieuwenhuysen, K. V.; Duerinckx, F.; Kuzma, I.; Gestel, D. v.; Beaucarne, G.; Poortmans, J., Progress in epitaxial deposition on low-cost substrates for thin-film crystalline silicon solar cells at IMEC. Journal of Crystal Growth 2006, 287 (2), 438-441.
45. Bergman, D. J., The dielectric constant of a composite material--A problem in classical physics. Physics Reports 1978, 43 (9), 377-407.
46. Thei, W., Optical properties of porous silicon. Surface Science Reports 1997, 29 (3-4), 91-192.
47. Okuya, M.; Nakade, K.; Kaneko, S., Porous TiO2 thin films synthesized by a spray pyrolysis deposition (SPD) technique and their application to dye-sensitized solar cells. Solar Energy Materials and Solar Cells 2002, 70 (4), 425-435.
48. Okuya, M., Prokudina, Nina A., Mushika, Katsuya, Kaneko, Shoji, TiO2 thin films synthesized by the spray pyrolysis deposition (SPD) technique. Journal of the European Ceramic Society
1999, 19 (6-7), 903-906.
49. Zhu, R.; Jiang, C.-Y.; Liu, X.-Z.; Liu, B.; Kumar, A.; Ramakrishna, S., Improved adhesion of interconnected TiO2 nanofiber network on conductive substrate and its application in polymer photovoltaic devices. Applied Physics Letters 2008, 93 (1), 013102-3.
50. Nazeeruddin, M. K.; Pechy, P.; Renouard, T.; Zakeeruddin, S. M.; Humphry-Baker, R.; Comte, P.; Liska, P.; Cevey, L.; Costa, E.; Shklover, V.; Spiccia, L.; Deacon, G. B.; Bignozzi, C. A.; Gratzel, M., Engineering of Efficient Panchromatic Sensitizers for Nanocrystalline TiO[sub 2]-Based Solar Cells. Journal of the American Chemical Society 2001, 123 (8), 1613.
51. Christophe, J. B.; Francine, A.; Pascal, C.; Marie, J.; Frank, L.; Valery, S.; Michael, G., Nanocrystalline Titanium Oxide Electrodes for Photovoltaic Applications. Journal of the American Ceramic Society 1997, 80 (12), 3157-3171.
52. Chen, J. Y.; Chen, H. C.; Lin, J. N.; Kuo, C. S., Effects of polymer media on electrospun mesoporous titania nanofibers. Mater. Chem. Phys. 2008, 107 (2-3), 480-487.
53. Shie, T.-Y. C., Jiun-Yu; Kuo, Changshu, Photoresponse of TiO2 nanofiber electrodes for photoelectrochemical water splitting. 234th ACS 2007.
54. Zheng, M.-p.; Gu, M.-y.; Jin, Y.-p.; Wang, H.-h.; Zu, P.-f.; Tao, P.; He, J.-b., Effects of PVP on structure of TiO2 prepared by the sol-gel process. Materials Science and Engineering B 2001, 87 (2), 197-201.
55. Fujimoto, M. O., Tomoya; Suzuki, Hisao; Koyama, Hiroshi; Tanaka, Junzo, Nanostructure of TiO2 nano-coated SiO2 particles. Journal of the American Ceramic Society 2005, 88 (11), 3264-3266.
56. Lai, Y. K.; Sun, L.; Chen, C.; Nie, C. G.; Zuo, J.; Lin, C. J., Optical and electrical characterization of TiO2 nanotube arrays on titanium substrate. Applied Surface Science 2005, 252 (4), 1101-1106.
57. Lettmann, C.; Hildenbrand, K.; Kisch, H.; Macyk, W.; Maier, W. F., Visible light photodegradation of 4-chlorophenol with a coke-containing titanium dioxide photocatalyst. Applied Catalysis B: Environmental 2001, 32 (4), 215-227.
58. Kroeze, J. E.; Savenije, T. J.; Vermeulen, M. J. W.; Warman, J. M., Contactless determination of the photoconductivity action spectrum, exciton diffusion length, and charge separation efficiency in polythiophene-sensitized TiO2 bilayers. Journal of Physical Chemistry B 2003, 107 (31), 7696-7705.
59. Goh, C.; Scully, S. R.; McGehee, M. D., Effects of molecular interface modification in hybrid organic-inorganic photovoltaic cells. Journal of Applied Physics 2007, 101 (11).
60. Mukherjee, K.; Teng, T. H.; Jose, R.; Ramakrishna, S., Electron transport in electrospun TiO2 nanofiber dye-sensitized solar cells. Applied Physics Letters 2009, 95 (1).
61. Song, M. Y.; Kim, D. K.; Ihn, K. J.; Jo, S. M.; Kim, D. Y., New application of electrospun TiO2 solid-state dye-sensitized solar electrode to cells. Synthetic Metals 2005, 153 (1-3), 77-80.
62. Onozuka, K.; Ding, B.; Tsuge, Y.; Naka, T.; Yamazaki, M.; Sugi, S.; Ohno, S.; Yoshikawa, M.; Shiratori, S., Electrospinning processed nanofibrous TiO2 membranes for photovoltaic applications. Nanotechnology 2006, 17 (4), 1026-1031.
63. Sommeling, P. M.; O'Regan, B. C.; Haswell, R. R.; Smit, H. J. P.; Bakker, N. J.; Smits, J. J. T.; Kroon, J. M.; van Roosmalen, J. A. M., Influence of a TiCl4 post-treatment on nanocrystalline TiO2 films in dye-sensitized solar cells. Journal of Physical Chemistry B 2006, 110 (39), 19191-19197.
64. Ito, S.; Liska, P.; Comte, P.; Charvet, R. L.; Pechy, P.; Bach, U.; Schmidt-Mende, L.; Zakeeruddin, S. M.; Kay, A.; Nazeeruddin, M. K.; Gratzel, M., Control of dark current in photoelectrochemical (TiO2/I--I-3(-)) and dye-sensitized solar cells. Chemical Communications 2005, (34), 4351-4353.
65. Zhu, R.; Jiang, C. Y.; Liu, X. Z.; Liu, B.; Kumar, A.; Ramakrishna, S., Improved adhesion of interconnected TiO2 nanofiber network on conductive substrate and its application in polymer photovoltaic devices. Applied Physics Letters 2008, 93 (1).
66. Huang, C. Y.; Hsu, Y. C.; Chen, J. G.; Suryanarayanan, V.; Lee, K. M.; Ho, K. C., The effects of hydrothermal temperature and thickness of TiO2 film on the performance of a dye-sensitized solar cell. Solar Energy Materials and Solar Cells 2006, 90 (15), 2391-2397.
67. Zeng, T. W.; Lo, H. H.; Chang, C. H.; Lin, Y. Y.; Chen, C. W.; Su, W. F., Hybrid poly (3-hexylthiophene)/titanium dioxide nanorods material for solar cell applications. Solar Energy Materials and Solar Cells 2009, 93 (6-7), 952-957.
68. Chang, C.-C.; Huang, C.-M.; Chang, Y.-H.; Kuo, C., Enhancement of light scattering and photoluminescence in electrospun polymer nanofibers. Opt. Express 2010, 18 (S2), A174-A184.
69. Fujihara, K.; Kumar, A.; Jose, R.; Ramakrishna, S.; Uchida, S., Spray deposition of electrospun TiO2 nanorods for dye-sensitized solar cell. Nanotechnology 2007, 18