Synthesis and Photovoltaic Properties of Conjugated Polymers Having Push-pull Structure according to the Type of Side-chain in the N-Substituted Phenothiazine

Push-pull 구조의 공액 고분자 합성 및 Phenothiazine의 질소 원자에 치환된 Side-chain에 따른 유기박막태양전지로의 특성 연구

  • Seong, Ki-Ho (Department of Industrial Chemistry, Sangmyung University) ;
  • Yun, Dae-Hee (Department of Industrial Chemistry, Sangmyung University) ;
  • Woo, Je-Wan (Department of Industrial Chemistry, Sangmyung University)
  • Received : 2014.09.22
  • Accepted : 2014.10.22
  • Published : 2014.12.10


In this study, a new series of conjugated polymer 3-(5-(5,6-bis(octyloxy)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-10-(4-(octyloxy)phenyl)-10H-phenothiazine (P1) and 3-(5-(5,6-bis(octyloxy)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazol-4-yl)thiophen-2-yl)-10-(4-((2-ethylhexyl)oxy)phenyl)-10H-phenothiazine (P2) were synthesised and organic photovoltaics (OPVs) properties were characterized. The push-pull structure polymer consisted of phenothiazine derivative as an electron donor and benzothiadiazole derivative as an electron acceptor. The aliphatic chain substituted aromatic ring was substituted at the position of N in phenothiazine for the electron-rich and improved solubility. Excellent thermal stabilities of P1 and P2 were confirmed by measured Td values as 321.9 and $323.7^{\circ}C$, respectively and the degrees of polymerization were 4,911 (P1) and 5,294 (P2). The maximum absorption wavelength of P1 and P2 were 549 and 566 nm, respectively. The device was fabricated and the OPVs property was measured. As a result, the power efficiency of conversion for P1 and P2 were 0.96 and 0.90%, respectively.


Phenothiazine;Benzothiadiazole;Push-pull structure;Side-chain effect;Conjugated polymer


Supported by : 상명대학교


  1. H. S. Yoo and Y. S. Park, Synthesis and Photovoltaic Properties of Conducting Polymers Based on Phenothiazine, Appl. Chem. Eng., 24, 93-98 (2013).
  2. W. Feiyan, Z. Daijun, C. Lie, and C. Yiwang, Photovoltaics of Donor.Acceptor Polymers Based on Benzodithiophene with Lateral Thiophenyl and Fluorinated Benzothiadiazole, J. Polym. Sci. Part A: Polym. Chem., 51, 1506-1511 (2013).
  3. D. H. Yun, H. S. Yoo, S. W. Heo, H. J. Song, D. K. Moon, and J. W. Woo, Synthesis and photovoltaic characterization of D/A structure compound based on N-substituted phenothiazine and benzothiadiazole, J. Ind. Eng. Chem., 19, 421-426 (2013).
  4. Z. Tan, I. Imae, Y. Ooyama, K. Komaguchi, J. Ohshita, and Y. Harima, Low bandgap polymers with benzodithiophene and bisthienylacrylonitrile units for photovoltaic applications, Eur. Polym. J., 49, 1634-1641 (2013).
  5. Z. Zhang, Q. Peng, D. Yang, Y. Chen, Y. Haung, X. Pu, Z. Lu, Q. Jiang, and Y. Liu, Novel conjugated polymers with planar backbone bearing acenaphtho[1,2-b]quinoxaline acceptor subunit for polymer solar cells, Synth. Met., 175, 21-29 (2013).
  6. Q. Peng, X. Liu, Y. Qin, J. Xu, M. Li, and L. Dai, Pyrazino[2,3-g]quinoxaline-based conjugated copolymers with indolocarbazole coplanar moieties designed for efficient photovoltaic applications, J. Mater. Chem., 21, 7714-7722 (2011).
  7. Y. R. Hong, J. Y. Ng, H. K. Wong, L. C. Moh, Y. J. Yip, Z. K. Chen, and T. B. Norsten, Synthesis and characterization of a series of low-bandgap copolymers based on cyclopenta[2,1-b:3,4-b']dithiophene and thienopyrroledione for photovoltaic applications, Sol. Energy Mater. Sol. Cells, 102, 58-65 (2012).
  8. Y. Li, Y. Chen, X. Liu, Z. Wang, X. Yang, Y. Tu, and X. Zhu, Controlling Blend Film Morphology by Varying Alkyl Side Chain in Highly Coplanar Donor Acceptor Copolymers for Photovoltaic Application, Macromolecular, 44, 6370-6381 (2011).
  9. B. Burkhart, P. P. Khlyabich, T. C. Canak, T. W. LaJoie, and B. C. Thompson, "Semi-Random" Multichromophoric rr-P3HT Analogues for Solar Photon Harvesting, Macromolecular, 44, 1242-1246 (2011).
  10. B. Burkhart, P. P. Khlyabich, and B. C. Thompson, Influence of the Ethylhexyl Side-Chain Content on the Open-Circuit Voltage in rr-Poly(3-hexylthiophene-co-3-(2-ethylhexyl)thiophene) Copolymers, Macromolecular, 45, 3740-3748 (2012).
  11. P. Morvillo, F. Parenti, R. Diana, C. Fontanesi, A. Mucci, F. Tassinari, and L. Schenetti, A novel copolymer from benzodithiophene and alkylsulfanyl-bithiophene: Synthesis, characterization and application in polymer solar cells, Sol. Energy Mater. Sol. Cells, 104, 45-52 (2012).
  12. Y. H. Seo, W. H. Lee, J. H. Park, C. Bae, Y. Hong, J. W. Park, and I. N. Kang, Side-Chain Effects on Phenothiazine-Based Donor-Acceptor Copolymer Properties in Organic Photovoltaic Devices, J. Polym. Sci. Part A: Polym. Chem., 50, 649-658 (2012).
  13. K. Colladet, S. Fourier, T. J. Cleij, L. Lutsen, J. Gelan, and D. Vanderzande, Low Band Gap Donor-Acceptor Conjugated Polymers toward Organic Solar Cells Applications, Macromolecular, 40, 65-72 (2007).
  14. J. Y. Lee, W. S. Shin, J. R. Haw, and D. K. Moon, Low band-gap polymers based on quinoxaline derivatives and fused thiophene as donor materials for high efficiency bulk-heterojunction photovoltaic cells, J. Mater. Chem., 19, 4938-4945 (2009).
  15. L. H. Chan, S. Y. Juang, M. C. Chen, and Y. J. Lin, A new series of random conjugated copolymers containing 3,4-diphenylmaleimide and thiophene units for organic photovoltaic cell applications, Polymer, 53, 2334-2346 (2012).
  16. S. K. Lee, W. H. Lee, J. M. Cho, S. J. Park, J. U. Park, W. S. Shin, J. C. Lee, I. N. Kang, and S. J. Moon, Synthesis and Photovoltaic Properties of Quinoxaline-Based Alternating Copolymers for High-Efficiency Bulk-Heterojunction Polymer Solar Cells, Macromolecular, 44, 5994-6001 (2011).
  17. Y. Liu, X. Wan, F. Wang, J. Zhou, C. Long, J. T, and Y. Chen, High-Performance Solar Cells using a Solution-Processed Small Molecule Containing Benzodithiophene Unit, Adv. Mater., 23, 5387-5391 (2011).
  18. Q. Shi, H. Fan, Y. Liu, J. Chen, L. Ma, W. Hu, Z. Shuai, Y. Li, and X. Zhan, Side Chain Engineering of Copolymers Based on Bithiazole and Benzodithiophene for Enhanced Photovoltaic Performance, Macromolecular, 44, 4230-4240 (2011).
  19. P. J. Homnick and P. M. Lahti, Modular electron donor group tuning of frontier energy levels in diarylaminofluorenone push pull molecules, Phys. Chem. Chem. Phys., 14, 11961-11968, (2012).
  20. X. Zhang, T. T. Steckler, R. R. Dasari, S. Ohira, W. J. Potscavage, Jr, S. P. Tiwari, S. Coppee, S. Ellinger, S. Barlow, J. L. Breadas, B. Kippelen, J. R. Reynolds, and S. R. Marder, Dithienopyrrole-based donor-acceptor copolymers: low band-gap materials for charge transport, photovoltaics and electrochromism, J. Mater. Chem., 20, 123-134 (2010).
  21. J. D. Azoulay, Z. A. Koretz, B. M. Wong, and G. C. Bazan, Bridgehead Imine Substituted Cyclopentadithiophene Derivatives: An Effective Strategy for Band Gap Control in Donor Acceptor Polymers, Macromolecular, 46, 1337-1342 (2013).
  22. Y. Zhang, J. Zou, C. C. Cheuh, H. L. Yip, and A. K. Y. Jen, Significant Improved Performance of Photovoltaic Cells Made from a Partially Fluorinated Cyclopentadithiophene/Benzothiadiazole Conjugated Polymer, Macromolecular, 45, 5427-5435 (2012).
  23. E, Zhou, J. Cong, K. Tajima, C. Yang, K. Hashimoto, Synthesis and Photovoltaic Properties of Donor-Acceptor Copolymer Based on Dithienopyrrole and Thienopyrroledione, Macromol. Chem. Phys., 212, 305-310 (2011).
  24. L. Huo, Z. Tan, X. Wang, Y. Zhou, M. Han, and Y. Li, Novel Two-Dimensional Donor-Acceptor Conjugated Polymers Containing Quinoxaline Units: Synthesis, Characterization, and Photovoltaic Properties, J. Polym. Sci. Part A: Polym. Chem., 46, 4038-4049 (2008).
  25. P. Karastatiris, J. A. Mikroyanndis, and I. K. Spiliopoulos, Bipolar Poly(p-phenylene vinylene)s Bearing Electron-Donating Triphenylamine or Carbazole and Electron-Accepting Quinoxaline Moieties, J. Polym. Sci. Part A: Polym. Chem., 46, 2367-2378 (2008).
  26. B. T. L. Nelson, T. M. Young, J. Liu, S. P. Mishra, J. A. Belot, C. L. Balliet, A. E. Javier, T. Kowalewski, and R. D. Mucullough, Transistor Paint: High Mobilities in Small Bandgap Polymer Semiconductor Based on the Strong Acceptor, Diketopyrrolopyrrole and Strong Donor, Dithienopyrrole, Adv. Mater., 22, 4617-4621 (2010).
  27. A. S. Hart, C. B. K. C., N. K. Subbaiyan, P. A. Karr, and F. D'Souza, Phenothiazine-Sensitized Organic Solar Cells: Effect of Dye Anchor Group Positioning on the Cell Performance, Appl. Mater. Interfaces, 4, 5813-5820 (2012).
  28. W. Li, W. S. C. Roelofs, M. Turbiez, M. M. Wienk, and R. A. J. Janssen, Polymer Solar Cells with Diketopyrrolopyrrole Conjugated Polymers as the Electron Donor and Electron Acceptor, Adv. Mater., 26, 3304-3309 (2014).
  29. W. Li, R. Qin, Y. Zhou, M. Andersson, F. Li, C. Zhang, B. Li, Z. Liu, Z. Bo, and F. Zhang, Tailoring side chains of low band gap polymers for high efficiency polymer solar cells, Polymer, 51, 3031-3038 (2010).
  30. A. Petrab, E. Bogdan, A. Terec, and I. Grosu, PODANDS WITH 10-ETHYL-3,7-DITHIENYL-10H-PHENOTHIAZINE CORE: SYNTHESIS AND STRUCTURAL ANALYSIS, Rev. Roum. Chim., 57(4-5), 345-351 (2012).
  31. X. Guo, M. Zhang, L. Huo, C. Cui, Y. Wu, J. Hou, and Y. Li, Poly(thieno[3,2 b]thiophene-alt-bithiazole): A D-A Copolymer Donor Showing Improved Photovoltaic Performance with Indene-$C_{60}$ Bisadduct Acceptor, Macromolecular, 45, 6930-6937 (2012).
  32. K. H. Seong, D. H. Yun, and J. W. Woo, Synthesis and Characterization of Power Conversion Efficiency of D/A Structure Conjugated Polymer Based on Benzothiadiazole-Benzodithiophene, Appl. Chem. Eng., 24, 537-543 (2013).
  33. D. H. Yun, H. S. Yoo, K. H. Seong, J. H. Lim, Y. S. Park, and J. W. Woo, Synthesis, Photovoltaic Properties and Side-chain effect of Copolymer Containing Phenothiazine and 2,1,3-Benzothiadiazole, Appl. Chem. Eng., 25, 487-496 (2014).
  34. M. Zhang, H. Fan, X. Guo, Y. Yang, S. Wang, Z. G. Zhang, J. Zhang, X. Zhan, and Y. Li, Synthesis and Photovoltaic Properties of Copolymers Based on Bithiophene and Bithiazole, J. Polym. Sci. Part A: Polym. Chem., 49, 2764-2754 (2011).
  35. S. Li, Z. He, J. Yu, S. Chen, A. Zhong, H. Wu, C. Zhong, J. Qin, and Z. Li, 2,3-Bis(5-Hexylthiophen-2-yl)-6,7-bis(octyloxy)-5,8-di(thio-phen-2-yl) quinoxaline: A Good Construction Block with Adjustable Role in the Donor-$\pi$-Acceptor System for Bulk-Heterojunction Solar Cells, J. Polym. Sci. Part A: Polym. Chem., 50, 2819-2828 (2012).
  36. P. Yang, M. Yuan, D. F. Zeigler, S. E. Watkins, J. A. lee, and C. K. Luscombe, Influence of fluorine substituents on the film dielectric constant and open-circuit voltage in organic photovoltaics, J. Mater. Chem. C, 2, 3278-3284 (2014).
  37. E. Zhou, J. Cong, S. Yamakawa, Q. Wei, M. Nakamura, K. Tajima, C. Yang, and K. Hashimoto, Synthesis of Thieno[3,4-b]pyrazine-Based and 2,1,3-Benzothiadiazole-Based Donor-Acceptor Copolymers and their Application in Photovoltaic Devices, Macromolecular, 43, 2873-2879 (2010).
  38. J. Y. Lee, K. W. Song, J. R. Ku, T. H. Sung, and D. K. Moon, Development of DA-type polymers with phthalimide derivatives as electron withdrawing units and a promising strategy for the enhancement of photovoltaic properties, Sol. Energy Mater. Sol. Cells, 95, 3377-3384 (2011).
  39. X. Xu, P. Cai, Y. Lu, N. S. Choon, J. Chen, X. Hu, and B. S. Ong, Synthesis and Characterization of Thieno[3,2-b]thiophene-isoindigo- based Copolymers as Electron Donor and Hole Transport Materials for Bulk-Heterojunction Polymer Solar Cells, J. Polym. Sci. Part A: Polym. Chem., 51, 424-434 (2013).
  40. L. Dou, J. Gao, E. Richard, J. You, C. C. Chen, K. C. Cha, Y. He, G. Li, and Y. Yang, Systematic Investigation of Benzodithiophene- and Diketopyrrolopyrrole-Based Low-Bandgap Polymers Designed for Single Junction and Tandem Polymer Solar Cells, J. Polym. Sci. Part A: Polym. Chem., 134, 10071-10079 (2012).
  41. J. Zhang, W. Cai, F. Huang, E. Wang, C. Zhong, S. Liu, M. Wang, C. Duan, T. Yang, and Y. Cao, Synthesis of Quinoxaline-Based Donor-Acceptor Narrow-Band-Gap Polymers and Their Cyclized Derivatives for Bulk-Heterojunction Polymer Solar Cell Applications, Macromolecular, 44, 894-901 (2011).