[1] [1] C. J. Brabec, N. S. Sariciftci and J. C. Hummelen, Adv. Funct. Mater. 11, 15 (2001).

[2] [2] Xin-fang Zhang, Zheng Xu, Su-ling Zhao, Fu-jun Zhang, Yan Li, Chun-yu Wu and Yue-ning Chen, Optoelectronics Letters 4, 257 (2008).

[3] [3] WU Bing, LI Yan-wu, LIU Peng-yi and HOU Lin-tao, Journal of Optoelectronics Laser 21, 363 (2010). (in Chinese)

[4] [4] TIAN Hui, XU Hao, YANG Li-ying, ZHANG Feng-ling and Inganas Olle, Journal of Optoelectronics Laser 21, 886 (2010). (in Chinese)

[5] [5] J. C. Bernède, Y. Berredjem, L. Cattin and M. Morsli, Appl. Phys. Lett. 91, 112111 (2007).

[6] [6] S. Sista, M. H. Park, Z. R. Hong, Y. Wu, J. H. Hou, W. L. Kwan, G. Li and Y. Yang, Adv. Mater. 22, 380 (2010).

[7] [7] M. Reyes-Reyes, K. Kim and D. L. Carroll, Appl. Phys. Lett. 87, 083506 (2005).

[8] [8] J. Y. Kim, K. Lee, N. E. Coates, D. Moses, T. Nguyen, M. Dante and A. J. Heeger, Science 317, 222 (2007).

[9] [9] S. H. Park, A. Roy, S. Beaupre, S. Cho, N. Coates, J. S. Moon, D. Moses, M. Leclerc, K. Lee and A. J. Heeger, Nature Photonics 3, 297 (2009).

[10] [10] C. W. Tang, Appl. Phys. Lett. 48, 183 (1986).

[11] [11] S. Pfuetzner, J. Meiss, A. Petrich, M. Riede and K. Leo, Appl. Phys. Lett. 94, 223307 (2009).

[12] [12] X. Xi, W. J. Li, J. Q. Wu, J. J. Ji, Zh. R. Shi and G. H. Li, Sol. Energy Mater. Sol. Cells 94, 2435 (2010).

[13] [13] Q. L. Song, F. Y. Li, H. Yang, H. R. Wu, X. Z. Wang, W. Zhou, J. M. Zhao, X. M. Ding, C. H. Huang and X. Y. Hou, Chem. Phys. Lett. 416, 42 (2005).

[14] [14] S. Heutz, P. Sullivan, B. M. Sanderson, S. M. Schultes and T.S. Jones, Sol. Energy Mater. Sol. Cells 83, 229 (2004).

[15] [15] H. Neugebauer, C. Brabec, J. C. Hummelen and N. S. Sariciftci, Sol. Energy Mater. Sol. Cells 61, 35 (2000).

[16] [16] J. M. Kroon, M. M. Wienk, W. J. H. Verhees and J. C. Hummelen, Thin Solid Films 403, 223 (2002).

[17] [17] Md. Khairul Hassan Bhuiyan and Tetsu Mieno, Thin Solid Films 441, 187 (2003).

[18] [18] M. P. de Jong, D. P. L. Simons, M. A. Reijme, L. J. van IJzendoorn, A. W. Denier van der Gon, M. J. A. de Voigt, H. H. Brongersma and R. W. Gymer, Synth. Met. 110, 1 (2000).

[19] [19] M. J rgensen, K. Norrman and F. C. Krebs, Sol. Cells 92, 686 (2008).

[20] [20] T. Ameri, G. Dennler, C. Lungenschmied and C. J. Brabec, Energy Environ. Sci. 2 , 347 (2009).

[21] [21] E. Reichmanis, H. Katz, C. Kloc and A. Maliakal, Bell Labs Technical Journal 10, 87 (2005).

[22] [22] F. C. Krebs, S. A. Gevorgyan and B. Gholamkhass, Sol. Energy Mater. Sol. Cells 93, 1968 (2009).

[23] [23] M. H. Petersen, S. A. Gevorgyan and F. C. Krebs, Macromolecules 41, 8986 (2008).

[24] [24] M. Rusu, J. Strotmann, M. Vogel, M. Ch. Lux-Steiner and K. Fostiropoulos, Appl. Phys. Lett. 90, 153511 (2007).