Browsing by Author "Balaganesan, Banumathy"

Now showing 1 - 2 of 2

A morphologically stable host material for efficient phosphorescent green and red organic light emitting devices
(2008-11-28)
Ho, Meng-Huan
;
Balaganesan, Banumathy
;
Chu, Ta-Ya
;
Chen, Teng-Ming
;
Chen, Chin H.
A carbazole-based host material, 4,4'-N,N'-[di(3, 6-di(t-butyl)carbazole]biphenyl (ttbCBP), with four t-butyl steric spacers on peripheral carbazole moieties was effectively synthesized through Friedel-Crafts Alkylation. Owing to the presence of sterically hindered t-butyl groups, ttbCBP exhibits a high glass transition temperature (175 degrees C) and is morphologically stable. This host material also preserves the characteristics of wide band-gap of 3.2 eV and high triplet energy of 2.64 eV. In addition, ttbCBP has been shown to be effective hosts for green and red phosphorescent emitters in organic electrophosphorescent devices. (C) 2008 Elsevier B.V. All rights reserved.
Blue Fluorescence and Bipolar Transport Materials Based on Anthracene and Their Application in OLEDs
(2012-06-01)
Ho, Meng-Huan
;
Balaganesan, Banumathy
;
Chen, Chin H. (Fred)
;
交大名義發表
;
National Chiao Tung University
The phenomenon of organic electroluminescence (EL) was first discovered from studies on anthracene crystals in the 1960s. Since then, its derivatives have been studied extensively in applications such as organic light-emitting diodes (OLEDs) and organic thin-film transistors because of their excellent EL, transport, and good electrochemical properties. A blue fluorescence emitter based on anthracene is also important in constructing hybrid tandem white OLEDs for lighting applications. This article provides a review about the development of blue host OLED materials based on molecules designed and derived from the core structure of anthracene and their application as bipolar charge-carrier transport materials in OLEDs. The recent development of efficient, stable, blue-doped p-i-n OLEDs with simplified device architecture based on the single common host 2-methyl-9,10-di(2-napthyl)anthracene, with its stable thin-film morphology, large band gap energy, high fluorescence quantum yield, and ambipolar charge-carrier transport properties, is also highlighted.