Macromolecular Research

The Polymer Society of Korea (한국고분자학회)
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Solvent-Induced Photoemissions of High-Energy Chromophores of Conjugated Polymer MEH-PPV: Role of Conformational Disorder

  • Traiphol, Rakchart (Laboratory of Advanced Polymers and Nanomaterials, Department of Chemistry, Faculty of Science, Naresuan University) ;
  • Charoenthai, Nipaphat (Laboratory of Advanced Polymers and Nanomaterials, Department of Chemistry, Faculty of Science, Naresuan University)
  • Published : 2008.04.30
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Abstract

This study examined the photoemission behaviors of isolated chains of poly[2-methoxy, 5-(2'-ethylhexyloxy)-1,4-phenylenevinylene](MEH-PPV) dispersed in various solvents including dichloromethane, chloroform and tetrahydrofuran(THF). A change in polymer-solvent interactions in these solutions caused the MEH-PPV chains to adopt different local conformations, which in turn affected their radiative de-excitation pathways. For the polymer in dichloromethane and chloroform, in which the conjugated chains are relatively extended, photoemission occurs mostly at the long chromophores with lowest HOMO-LUMO energy gap. Their emission spectra showed a main peak at ${\sim}560\;nm$. Dual photoemission of high- and low-energy chromophores was observed when the conjugated chains were forced to partially collapse in a poor solvent THF. Novel high-energy peaks and a typical low-energy peak were detected at ${\sim}414\;nm$ and ${\sim}554\;nm$, respectively. The observation of the high-energy peaks indicates significant suppression of the intrachain energy transfer process, which was attributed to the increase in conformational disorder in the partially collapsed coils. An analysis of the excitation spectra suggests that the high-energy peaks belong to short chromophores constituting of one or two repeat units. This study systematically investigated the effects of polymer concentration, temperature and single bond defects along the backbone on the photoemission of the high-energy chromophores.

Keywords

References

  1. J. H. Burroughes, D. D. C. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns, and A. B. Holmes, Nature, 347, 539 (1990) https://doi.org/10.1038/347539a0
  2. R. H. Friend, R. W. Gymer, A. B. Holmes, J. H. Burroughes, R. N. Marks, C. Taliani, D. D. C. Bradley, D. A. Dossantos, J. L. BrZdas, M. Lsgdlund, and W. R. Salaneck, Nature, 397, 121 (1999) https://doi.org/10.1038/16393
  3. A. Kraft, A. C. Grimsdale, and A. B. Holmes, Angew. Chem. Int. Ed., 37, 402 (1998) https://doi.org/10.1002/(SICI)1521-3773(19980302)37:4<402::AID-ANIE402>3.0.CO;2-9
  4. H. Spanggaard and F. C. Krebs, Sol. Energy Mater. Sol. Cells, 83, 125 (2004) https://doi.org/10.1016/j.solmat.2004.02.021
  5. C. J. Brabec, N. S. Sariciftci, and J. C. Hummelen, Adv. Funct. Mater., 11, 15 (2001) https://doi.org/10.1002/1616-3028(200102)11:1<15::AID-ADFM15>3.0.CO;2-A
  6. D. T. McQuade, A. E. Pullen, and T. M. Swager, Chem. Rev., 100, 2537 (2000) https://doi.org/10.1021/cr9801014
  7. J. M. Tour, Acc. Chem. Res., 33, 791 (2000) https://doi.org/10.1021/ar0000612
  8. W. Holzer, A. Penzkofer, H. Tillmann, and H. H. Hsrhold, Synth. Met., 140, 155 (2004) https://doi.org/10.1016/S0379-6779(03)00356-4
  9. G. Padmanaban and S. Ramakrishnan, J. Am. Chem. Soc., 122, 2244 (2000) https://doi.org/10.1021/ja9932481
  10. G. Padmanaban and S. Ramakrishnan, J. Phys. Chem. B, 108, 14933 (2004) https://doi.org/10.1021/jp048994t
  11. K. F. Lin, Y. L. Fan, and H. L. Chow, Polym. Int., 55, 938 (2006) https://doi.org/10.1002/pi.2043
  12. C. L. Gettinger, A. J. Heeger, J. M. Drake, and D. J. Pine, J. Chem. Phys., 101, 1673 (1994) https://doi.org/10.1063/1.468438
  13. D. Hu, J. Yu, K. Wong, B. Bagchi, P. J. Rossky, and P. F. Barbara, Nature, 405, 1030 (2000) https://doi.org/10.1038/35016520
  14. D. Hu, J. Yu, G. Padmanaban, S. Ramakrishnan, and P. F. Barbara, Nano Lett., 2, 1121 (2002) https://doi.org/10.1021/nl015661o
  15. T.-Q. Nguyen, V. Doan, and B. J. Schwartz, J. Chem. Phys., 110, 4068 (1999) https://doi.org/10.1063/1.478288
  16. B. J. Schwartz, Annu. Rev. Phys. Chem., 54, 141 (2003) https://doi.org/10.1146/annurev.physchem.54.011002.103811
  17. B. G. Sumpter, P. Kumar, A. Mehta, M. D. Barnes, W. A. Shelton, and R. J. Harrison, J. Phys. Chem. B, 109, 7671 (2005) https://doi.org/10.1021/jp0446534
  18. P. Kumar, A. Mehta, S. M. Mahurin, S. Dai, M. D. Dadmun, B. G. Sumpter, and M. D. Barnes, Macromolecules, 37, 6132 (2004) https://doi.org/10.1021/ma048917w
  19. P. F. Barbara, A. J. Gesquiere, S.-J. Park, and Y. J. Lee, Acc. Chem. Res., 38, 602 (2005) https://doi.org/10.1021/ar040141w
  20. R. Traiphol, P. Sanguansat, T. Srikhirin, T. Kerdcharoen, and T. Osotchan, Macromolecules, 39, 1165 (2006) https://doi.org/10.1021/ma052512+
  21. R. Traiphol, N. Charoenthai, T. Srikhirin, T. Kerdcharoen, T. Osotchan, and T. Maturos, Polymer, 48, 813 (2007) https://doi.org/10.1016/j.polymer.2006.12.003
  22. R. Traiphol, T. Srikhirin, T. Kerdcharoen, T. Osotchan, N. Scharnagl, and R. Willumeit, Eur. Polym. J., 43, 478 (2007) https://doi.org/10.1016/j.eurpolymj.2006.11.022
  23. Y. H. Kim, H. O. Lee, S. O. Jung, and S. K. Kwon, Macromol. Res., 11, 194 (2003) https://doi.org/10.1007/BF03218352
  24. Y. H. Kim, H. O. Lee, K. S. Lee, and S. K. Kwon, Macromol. Res., 11, 471 (2003) https://doi.org/10.1007/BF03218978
  25. F. Schindler, J. M. Lupton, J. Feldmann, and U. Scherf, Proc. Natl. Acad. Sci. USA, 101, 14695 (2004)
  26. E. Hennebicq, C. Deleener, J.-L. BrZdas, G. D. Scholes, and D. Beljonne, J. Chem. Phys., 125, 054901 (2006) https://doi.org/10.1063/1.2221310
  27. O. Narwark, S. C. J. Meskers, R. Peetz, E. $Thorn-Cs{ \ddag}nyi$, and H. BSssler, Chem. Phys., 294, 1 (2003) https://doi.org/10.1016/S0301-0104(03)00334-3
  28. O. Narwark, A. Gerhard, S. C. J. Meskers, S. Brocke, E. $Thorn-Cs{\ddag}nyi$, and H. BSssler, Chem. Phys., 294, 17 (2003) https://doi.org/10.1016/S0301-0104(03)00335-5
  29. S. R. Amrutha and M. Jayakannan, J. Phys. Chem. B, 110, 4083 (2006) https://doi.org/10.1021/jp056522o
  30. J. Seixas de Melo, J. Pina, H. D. Burrows, R. E. Di Paolo, and A. L. Maanita, Chem. Phys., 330, 449 (2006) https://doi.org/10.1016/j.chemphys.2006.09.016
  31. S. Suramitr, T. Kerdcharoen, T. Srikhirin, and S. Hannongbua, Synth. Met., 155, 27 (2005) https://doi.org/10.1016/j.synthmet.2005.05.016
  32. G. R. Hayes, I. D. W. Samuel, and R. T. Phillips, Phys. Rev. B, 52, R11569 (1995) https://doi.org/10.1103/PhysRevB.52.R11569
  33. J.-L. BrZdas, D. Beljonne, V. Coropceanu, and J. Cornil, Chem. Rev., 104, 4971 (2004) https://doi.org/10.1021/cr040084k
  34. E. Hennebicq, G. Pourtois, G. D. Scholes, L. M. Herz, D. M. Russell, C. Silva, S. Setayesh, A. C. Grimsdale, K. MYllen, J.-L. BrZdas, and D. Beljonne, J. Am. Chem. Soc., 127, 4744 (2005) https://doi.org/10.1021/ja0488784
  35. B. Valeur, Molecular Fluorescence : Principles and Applications, Wiley-VCH, Weinheim, 2001, pp. 50-52
  36. S. Westenhoff, W. J. D. Beenken, A. Yartsev, and N. C. Greenham, J. Chem. Phys., 125, 154903 (2006) https://doi.org/10.1063/1.2358682
  37. M. M. -L. Grage, P. W. Wood, A. Ruseckas, T. Pullerits, W. Mitchell, P. L. Burn, I. D. W. Samuel, and V. Sunstrsm, J. Chem. Phys., 118, 7644 (2003) https://doi.org/10.1063/1.1562190