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Characterization of white electroluminescent devices fabricated using conjugated polymer blends

Published online by Cambridge University Press:  03 March 2011

Do-Hoon Hwang ,
Moo-Jin Park ,
Suk-Kyung Kim ,
Nam-Heon Lee ,
Changhee Lee ,
Yong-Bae Kim  and
Hong-Ku Shim
Do-Hoon Hwang*
Affiliation:
Department of Applied Chemistry, Kumoh National Institute of Technology, Kumi 730-701, Korea
Moo-Jin Park
Affiliation:
Department of Applied Chemistry, Kumoh National Institute of Technology, Kumi 730-701, Korea
Suk-Kyung Kim
Affiliation:
Department of Applied Chemistry, Kumoh National Institute of Technology, Kumi 730-701, Korea
Nam-Heon Lee
Affiliation:
Department of Physics, Inha University, Incheon 402-751, Korea
Changhee Lee
Affiliation:
School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-744, Korea
Yong-Bae Kim
Affiliation:
Liquid Crystal Research Center, Department of Chemistry, Kon-Kuk University, Seoul 143-701, Korea
Hong-Ku Shim
Affiliation:
Center for Advanced Functional Polymers, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology, Taejon 305-701, Korea
*
a) Address all correspondence to this author. e-mail: dhhwang@kumoh.ac.kr
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Abstract

We report the characterization of white light emitting devices fabricated using conjugated polymer blends. Blue emissive poly[9,9-bis(4′-n-octyloxyphenyl)fluorene-2,7-diyl-co-10-(2′-ethylhexyl)phenothiazine-3,7-diyl] [poly(BOPF-co-PTZ)] and red emissive poly(2-(2′-ethylhexyloxy)-5-methoxy-1,4-phenylenevinylene) (MEH-PPV) were used in the blends. The inefficient energy transfer between these blue and red light emitting polymers (previously deduced from the photoluminscence (PL) spectra of the blend films) enables the production of white light emission through control of the blend ratio. The PL and electroluminescence (EL) emission spectra of the blend systems were found to vary with the blend ratio. The EL devices were fabricated in the indium tin oxide [poly(3,4-ethylenedioxy-thiophene)-poly(styrenesulfonate)] (ITO/PEDOT-PSS)blend/LiF/Al configuration, and white light emission was obtained for one of the tested blend ratios.

Keywords

PolymerBlendElectronic material
Type
Articles—Organic Electronics Special Section
Information
Journal of Materials Research , Volume 19 , Issue 7 , July 2004 , pp. 2081 - 2086
Copyright
Copyright © Materials Research Society 2004

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