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HomeKey Engineering MaterialsKey Engineering Materials Vol. 751Charged Iridium(III) Complexes with Varied Side...

Charged Iridium(III) Complexes with Varied Side Chain Length in Organic Light Emitting Diodes

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Abstract:

The four varied side chains of charged iridium(III) complexes were synthesized and characterized for organic light emitting diodes. The core materials were designed with 9,9-bis(4-methoxyphenyl)-4,5-diazafluorene as the bulky N^N ligand which prevent the π-π stacking interaction in the solid state. Their photophysical and electrochemical properties were investigated. OLEDs were fabricated with the structure ITO/PEDOT:PSS/ PVK:complex (10:7 by weight)/ TPBi/LiF/Al. The similar colors were obtained with varied OLEDs performances. We concluded that the long alkyl chains affected to the excellent film-forming property of emitting layer. Therefore, the device based on the n-octyl chain namely [(9,9-bis(4-octyloxyphenyl)-9H-cyclopentadipyridine-N-N′)-bis-(2-phenylpyridine-C^2′,N)-iridium(III)] haxafluorophosphate (C8) showed the maximum current efficiency and brightness of 11.37 cd/A and 3,926 cd/m², respectively.

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Materials Science and Technology IX

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Periodical:

Key Engineering Materials (Volume 751)

Pages:

500-506

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.751.500

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Online since:

August 2017

Authors:

Natsiri Wongsang, Kittiya Wongkhan, Laongdao Kangkeaw, Somboon Sahasitthiwat, Rukkiat Jitchati*

Keywords:

4,5-Diazafluorene, Charged Complex, Iridium (III), OLEDs

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© 2017 Trans Tech Publications Ltd. All Rights Reserved

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