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Highly Efficient Multifunctional Phosphorescent Dendrimers Consisting of an Iridium-Complex Core and Charge-Transporting Dendrons for Organic Light-Emitting Devices

Published online by Cambridge University Press:  01 February 2011

Toshimitsu Tsuzuki
Affiliation:
Science and Technical Research Laboratories, Japan Broadcasting Corporation (NHK), 1-10-11 Kinuta, Setagaya-ku, Tokyo 157-8510, Japan
Nobuhiko Shirasawa
Affiliation:
Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8787, Japan
Toshiyasu Suzuki
Affiliation:
Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8787, Japan
Shizuo Tokito
Affiliation:
Science and Technical Research Laboratories, Japan Broadcasting Corporation (NHK), 1-10-11 Kinuta, Setagaya-ku, Tokyo 157-8510, Japan
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Abstract

We report a novel class of emitting materials for use in the organic light-emitting devices (OLEDs): multifunctional phosphorescent dendrimers that have a phosphorescent core and have charge transporting dendrons. We have synthesized first-generation and second-generation dendrimers consisting of a fac-tris(2-phenylpyridine)iridium [Ir(ppy)3] core and hole transporting phenylcarbazole-based dendrons. Smooth amorphous films of these dendrimers were formed by spin-coating them from solutions. The OLEDs using the dendrimer exhibited bright green or yellowish-green emission from the Ir(ppy)3 core. The external quantum efficiency of the OLED using the mixture film of the first-generation dendrimer and an electron-transporting material was as high as 7.6%.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

Refereces

1 Hecht, S. and Fréchet, J. M. J., Angew. Chem. Int. Ed. 40, 74 (2001).Google Scholar
2 Wang, P.-W., Liu, Y.-J., Devadoss, C., Bharathi, P. and Moore, J. S., Adv. Mater. 8, 237 (1996).Google Scholar
3 Halim, M., Pillow, J. N. G., Samuel, I. D. W. and Burn, P. L., Adv. Mater. 11, 371 (1999).Google Scholar
4 Freeman, A. W., Koene, S. C., Malenfant, P. R. L., Thompson, M. E. and Fréchet, J. M. J., J. Am. Chem. Soc. 122, 12385 (2000).Google Scholar
5 Ma, D., Lupton, J. M., Samuel, I. D. W. and Lo, S.-C., Burn, P. L., Appl. Phys. Lett. 81, 2285 (2002).Google Scholar
6 Markham, J. P. J., Lo, S.-C., Magennis, S. W., Burn, P. L. and Samuel, I. D. W., Appl. Phys. Lett. 80, 2645 (2002).Google Scholar
7 Lo, S.-C., , Nigel, Male, A. H., Markham, J. P. J., Magennis, S. W., Burn, P. L., Salata, O. V. and Samuel, I. D. W., Adv. Mater. 14, 975 (2002).Google Scholar
8 Anthopoulos, T. D., Markham, J. P. J., Namdas, E. B., Samuel, I. D. W., Lo, S.-C. and Burn, P. L., Appl. Phys. Lett. 82, 4824 (2003).Google Scholar
9 Lo, S.-C., Namdas, E. B., Burn, P. L. and Samuel, I. D. W., Macromolecules 36, 9721 (2003).Google Scholar
10 Anthopoulos, T. D., Frampton, M. J., Namdas, E. B., Burn, P. L. and Samuel, I. D. W., Adv. Mater. 16, 557 (2004).Google Scholar
11 Baldo, M. A., Lamansky, S., Burrows, P. E., Thompson, M. E. and Forrest, S. R., Appl. Phys. Lett. 75, 4 (1999).Google Scholar
12 Miyaura, N., Ishiyama, T., Sasaki, H., Ishikawa, M., Sato, M. and Suzuki, A., J. Am. Chem. Soc. 111, 314 (1989).Google Scholar
13 Sakamaki, K., Ohshita, J., Kunai, A., Nakao, H., Adachi, A. and Okita, K., Appl. Organomet. Chem. 15, 604 (2001).Google Scholar
14 Dedeian, K., Djurovich, P. I., Garces, F. O., Carlson, G. and Watts, R. J., Inorg. Chem. 30, 1685 (1991).Google Scholar
15 Tsuzuki, T., Shirasawa, N., Suzuki, T. and Tokito, S., Adv. Mater. 15, 1455 (2003).Google Scholar