| Autor: |
Meulenkamp, E.A., Aar, R. van, Bastiaansen, J.J.A.M., Biggelaar, A.J.M. van den, Börner, H., Brunner, K., Büchel, M., Dijken, A. van, Kiggen, N.M.M., Kilitziraki, M., Kok, M.M. de, Langeveld, B.M.W., Ligter, M.P.H., Vulto, S.I.E., Weijer, P. van de, Winter, S.H.P.M. de |
| Přispěvatelé: |
TNO Industrie |
| Jazyk: |
angličtina |
| Rok vydání: |
2004 |
| Předmět: |
|
| Zdroj: |
Heremans, P.L.Muccini, M.Hofstraat, H., Organic Optoelectronics and Photonics, 28-30 April 2004, Strasbourg, France, 5464, 90-103 |
| Popis: |
We present results and a discussion of highly efficient polymer Light-Emitting Diodes (polymer LEDs, PLEDs). The external quantum efficiency in current standard devices reaches up to 2-4% only. We have explored two routes to enhance this value. In the first route, PEDOT/PSS is replaced with a novel anode or hole injection layer. The efficiency with some Light Emitting Polymers (LEP) is improved significantly, resulting in an efficacy of 35 cd/A for a yellow emitting poly-(para-phenylene-vinylene) and 20 cd/A for a blue emitting poly-(spirobifluorene). We attribute the major improvement compared to standard devices, where about 10 and 5 cd/A are obtained, respectively, to a combination of improved exciton formation efficiency and light out-coupling efficiency, and to less quenching of the radiative decay under actual device operating conditions. In the second route, we developed a new host polymer with high triplet energy such that transition metal-based green-emitting phosphorescent dyes can be used without significant back transfer of triplet excitons to the polymer host. First results using this system showed about 25 cd/A using a soluble green Ir-based emitter. Importantly, all data are obtained in a standard two-layer device of a hole transport/injection layer and the LEP. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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