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Title: Novel Light-Emitting Organic Materials with Variable Electron and Hole Conductivities

Abstract

Novel organic materials are constructed by attaching monodisperse oligofluorenes to a hole- or an electron-conducting core through a flexible spacer. These materials exhibit desirable properties for use in polarized and unpolarized light-emitting diodes, such as the ability to form morphologically stable glassy liquid crystalline and amorphous films with elevated glass transition temperatures, capability for full-color emission, tunability of charge injection and transport, and ultimately achieving superior OLED device efficiency and lifetime.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Laboratory for Laser Energetics, University of Rochester, Rochester, NY
Sponsoring Org.:
USDOE
OSTI Identifier:
859943
Report Number(s):
DOE/SF/19460-639
1599; 2005-158; TRN: US200721%%305
DOE Contract Number:
FC52-92SF19460
Resource Type:
Conference
Resource Relation:
Journal Name: Liquid Crystals IX, edited by I.-C. Khoo (SPIE, Belingham, WA, 2005), Vol. 5936-18.; Conference: SPIE 50th Annual Meeting, San Diego, CA, 31 July-4 August 2005
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ORGANIC FLUORINE COMPOUNDS; SYNTHESIS; LIGHT EMITTING DIODES; SERVICE LIFE; ELECTRIC CONDUCTIVITY; HOLES; glassy liquid crystals; molecular glasses; organic light-emitting diodes; polarized light emission

Citation Formats

Chen, A.C.-A., Wallace, J.U., Zeng, L., Wei, S.K.-H., and Chen, S.H.. Novel Light-Emitting Organic Materials with Variable Electron and Hole Conductivities. United States: N. p., 2005. Web.
Chen, A.C.-A., Wallace, J.U., Zeng, L., Wei, S.K.-H., & Chen, S.H.. Novel Light-Emitting Organic Materials with Variable Electron and Hole Conductivities. United States.
Chen, A.C.-A., Wallace, J.U., Zeng, L., Wei, S.K.-H., and Chen, S.H.. Thu . "Novel Light-Emitting Organic Materials with Variable Electron and Hole Conductivities". United States. doi:.
@article{osti_859943,
title = {Novel Light-Emitting Organic Materials with Variable Electron and Hole Conductivities},
author = {Chen, A.C.-A. and Wallace, J.U. and Zeng, L. and Wei, S.K.-H. and Chen, S.H.},
abstractNote = {Novel organic materials are constructed by attaching monodisperse oligofluorenes to a hole- or an electron-conducting core through a flexible spacer. These materials exhibit desirable properties for use in polarized and unpolarized light-emitting diodes, such as the ability to form morphologically stable glassy liquid crystalline and amorphous films with elevated glass transition temperatures, capability for full-color emission, tunability of charge injection and transport, and ultimately achieving superior OLED device efficiency and lifetime.},
doi = {},
journal = {Liquid Crystals IX, edited by I.-C. Khoo (SPIE, Belingham, WA, 2005), Vol. 5936-18.},
number = ,
volume = ,
place = {United States},
year = {Thu Nov 17 00:00:00 EST 2005},
month = {Thu Nov 17 00:00:00 EST 2005}
}

Conference:
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  • We report the design, synthesis, thermal, and photophysical properties of two phosphine oxide based electron transport/hole blocking materials, 2,6-bis(4-(diphenylphosphoryl)phenyl)pyridine (BM-A11) and 2,4-bis(4-(diphenyl-phosphoryl)phenyl)pyridine (BM-A10) for blue electrophosphorescent organic light emitting devices (OLEDs). The use of these materials in blue OLED with iridium (III) bis[(4,6-difluorophenyl)-pyridinato-N,C2’]picolinate (Firpic) as the phosphor was demonstrated. Using the dual host device architecture with BM-A10 as the ETM yields a maximum EQE of 8.9% with a power efficiency of 21.5 lm/W (4.0V and 35 cd/m2). When BM-A11 is used as the ETM, the maximum EQE and power efficiency improves to 14.9% and 48.4 lm/W, respectively (3.0V and 40more » cd/m2).« less
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