Device applications of charge transport in discotic liquid crystals

(Note: The full text of this document is currently only available in the PDF Version )

Neville Boden, Richard J. Bushby, Jonathan Clements and Bijan Movaghar


Abstract

We discuss some of the unique structural and electronic properties of discotic liquid crystals, particularly the nature of the ‘band structure’, and of charge injection from metal electrodes. Attempts have been made to use conducting discotic liquid crystals in electroluminescent devices and in gas sensors. The latter are created by spin-coating a thin film of discotic liquid crystals onto an array of interdigitated electrodes. We discuss the temperature dependence of the conductivity of these new systems, analyse the mechanism of charge diffusion and the effect of adsorbed gases.


References

  1. S. Chandrasekhar and G. S. Raganath, Rep. Prog. Phys., 1990, 53, 57 CrossRef CAS .
  2. N. Boden, R. J. Bushby and A. N. Cammidge, J. Am. Chem. Soc., 1995, 117, 924 CrossRef CAS ; N. Boden, R. J. Bushby and A. N. Cammidge, Liq. Cryst., 1995, 18, 673 CAS .
  3. T. Christ, V. Stumpflen and J. H. Wendorff, Macromol. Rapid Commun., 1997, 18, 93 CAS .
  4. M. A. Bates and G. R. Luckhurst, J. Chem. Phys., 1996, 104, 6696 CrossRef CAS .
  5. J. H. Williams, Acc. Chem. Res., 1993, 26, 593 CrossRef CAS .
  6. A. M. Levelut, J. Phys. Lett., 1979, 40, L81 Search PubMed .
  7. T. J. Phillips and J. C. Jones, Liq. Cryst., 1994, 16, 805 .
  8. R. Lucht and C. Bahr, Phys. Rev. Lett., 1997, 78, 3487 CrossRef CAS .
  9. I. G. Voigt-Martin, R. W. Garbella and M. Schumacher, Liq. Cryst., 1994, 17, 775 CAS .
  10. N. Boden, R. J. Bushby, J. Clements, M. Jesudason, P. F. Knowles and G. Williams, Chem. Phys. Lett., 1988, 152, 94 CrossRef CAS .
  11. D. Adam, F. Closs, T. Frey, D. Funhoff, D. Haarer, H. Ringsdorf, P. Schumacher and S. K. Siemensmeyer, Phys. Rev Lett., 1993, 70, 457 CrossRef CAS ; D. Adam, P. Schumacher, J. Simmmerer, K. H. Etzbach, H. Ringsdorf and D. Haarer, Nature, 1994, 371, 141 CrossRef CAS .
  12. H. Bengs, F. Closs, T. Frey, D. Funhoff, H. Ringsdorf and K. Siemensmeyer, Liq. Cryst., 1993, 15, 565 CrossRef CAS ; D. Adam, W. Rohmhildt and D. Haarer, in Metallomesogens and Discotic Liquid Crystals, ONRI, 1995, Osaka, Japan, p. 100 Search PubMed .
  13. N. Boden, J. Clements, R. J. Bushby, B. Movaghar, K. Donovan and T. Kreouzis, Phys. Rev. B, 1995, 52, 13 274 CrossRef CAS .
  14. B. Movaghar, Z. Phys. B, 1991, 85, 23 .
  15. R. Dong, D. Goldfarb, M. E. Moseley, Z. Luz and H. Zimmermann, J. Phys. Chem., 1984, 88, 3148 CrossRef CAS .
  16. P. Borsenberger, L. Pautmeier and H. Baessler, J. Chem. Phys., 1991, 94, 5447 CrossRef CAS ; H. Baessler, in the press ; T. Holstein, Ann. Phys., 1959, 8, 325 and 343 Search PubMed .
  17. N. Boden, R. J. Bushby, J. Clements and B. Movaghar, J. Appl. Phys., 1995, 33, 3207 .
  18. A. Bacher, I. Bleyel, C. Erdelen, D. Haarer, W. Paulus and H. W. Schmidt, Adv. Mater., 1997, 9, 1031 CrossRef CAS .
  19. T. Christ, B. Gluesen, A. Greiner, A. Kettner, R. Sander, V. Stuemfplen, V. Tsukruk and J. Wendorff, Adv. Mater., 1997, 9, 48 CrossRef CAS .
  20. M. Funahashi and J.-I. Hanna, Phys. Rev. Lett., 1997, 78, 2184 CrossRef CAS ; D. Markovitsi, I. Lecuyer, P. Lianos and J. Malthete, J. Chem. Soc., Faraday Trans., 1991, 87, 1785 and J. Phys. Chem. B, 1998, 102, 4697 Search PubMed .
  21. M. Pope and S. Swenberg, Electronic Processes in Organic Materials, Oxford University Press, 1982 Search PubMed .
  22. E. Sirota, P. Pershan, S. Amador and L. Sorensen, Phys. Rev. A, 1987, 35, 2283 CrossRef CAS .
  23. B. Jerome, Rep. Prog. Phys., 1991, 54, 391 CrossRef CAS .
  24. J. G. Dash, Contemp. Phys., 1989, 30, 89 CAS .
  25. D. Schlauf and C. Bahr, Phys. Rev. B, 1998, 57, R 1235 Search PubMed .
  26. J. M. Warman, M. P. de Haas, K. J. Smit, M. N. Paddon-Row and J. F. van der Pol, Mol. Cryst. Liq. Cryst., 1990, 183, 375 CAS ; A. M. van de Craats, J. M. Warman, K. Muellen, Y. Geerts and J. D. Brand, Adv. Mater., 1998, 10, 36 CrossRef CAS .
  27. N. Boden, R. J. Bushby, J. Clements and B. Movaghar, British Liquid Crystal Society Meeting, Leeds ( 1998) ; J. Clements, N. Boden, T. Gibson, R. Chandler, J. Hulbert and E. A. Ruck-Keene, Sens. Actuators, 1998, 47, 37 Search PubMed .
  28. Kolesar, USP 5 045 285, Sept 3 1991, ‘Gaseous component Identification with Polymeric Film Sensors’ .
  29. J. Thoen, in Handbook of Liquid Crystals Vol. 1, ed. D. Demus, J. Goodby, G. Gray, H. Spiess and V. Vill, Wiley-VCH, 1998, p. 310 Search PubMed .
  30. N. Boden, R. J. Bushby, J. Clements and B. Movaghar, unpublished work .
  31. L. Siebbeles and B. Movaghar, J. Chem. Phys., 1999, 10, 10162 CrossRef .
  32. D. P. Yu, Z. G. Bai, J. J. Wang, Y. H. Zou, W. Qian, J. S. Fu, H. Z. Zhang and Y. Ding, Appl. Phys. Lett., 1998, 73, 677 CrossRef .
  33. G. C. Xiong and S. Q. Feng, Phys. Rev. B Rapid Commun., 1999, 59, 1645 Search PubMed .
  34. N. Boden and B. Movaghar, in Handbook of Liquid Crystals, Vol. 2B, ed. D. Demus, J. Goodby, G. Gray, H. Spiess and V. Vill, Wiley-VCH, 1998, p. 781 Search PubMed .
  35. N. Boden, R. J. Bushby and A. N. Cammidge, J. Am. Chem. Soc., 1995, 117, 924 CrossRef CAS .
Click here to see how this site uses Cookies. View our privacy policy here.