Optimization of the Luminescence Efficiencies in Solution-Processed Phosphorescent Dendrimers

Ribierre, J.-C., Stevenson, S. G., Samuel, I. D. W., Staton, S. V. and Burn, P. L. (2007) Optimization of the Luminescence Efficiencies in Solution-Processed Phosphorescent Dendrimers. IEEE Journal of Display Technology, 3 2: 233-237. doi:10.1109/JDT.2007.896744


Author Ribierre, J.-C.
Stevenson, S. G.
Samuel, I. D. W.
Staton, S. V.
Burn, P. L.
Title Optimization of the Luminescence Efficiencies in Solution-Processed Phosphorescent Dendrimers
Journal name IEEE Journal of Display Technology   Check publisher's open access policy
ISSN 1551-319X
Publication date 2007-06
Year available 2007
Sub-type Article (original research)
DOI 10.1109/JDT.2007.896744
Volume 3
Issue 2
Start page 233
End page 237
Total pages 5
Place of publication Weinheim
Publisher Wiley - VCH Verlag GmbH & Co KGaA
Collection year 2007
Language eng
Subject 020504 Photonics, Optoelectronics and Optical Communications
Abstract We demonstrate that photoluminescence (PL) quantum yield and PL lifetime of fac-tris(2-phenylpyridyl) iridium(III) [Ir(ppy)3]-cored dendrimers in neat film and dispersed into a 4,4'-bis(N-carbazolyl)biphenyl host can be significantly improved by a simple adjustment of the solution preparation. Quenching of the PL in these materials is due to an energy transfer of the triplet excitons to less-emissive sites and can be reduced by blending the phosphorescent molecules into a suitable wide energy gap host or by increasing the number of attached dendrons. We show here that the concentration of these quenchers can also be controlled by changing the time spent by the dendrimer solution under illumination prior to spin-coating. By optimizing the film preparation procedure, the external efficiency of devices made from neat dendrimer films was increased from 2% to 10%
Keyword Dendrimer
OLED
phosphorescence
photostability
solution-processing
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Document type: Journal Article
Sub-type: Article (original research)
Collections: Faculty of Science Publications
School of Chemistry and Molecular Biosciences
 
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