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Indexed by:期刊论文

Date of Publication:2013-04-01

Journal:DYES AND PIGMENTS

Included Journals:SCIE、EI

Volume:97

Issue:1

Page Number:155-161

ISSN No.:0143-7208

Key Words:Phosphorescent OLED; Host; Tridurylborane; Oligo-fluorene; Solution-processing; Small molecular host

Abstract:Novel tridurylboranes based molecules with oligofluorene endcaps, namely tris[(9,9-dioctylfluoren-2-yl)duryl]borane (DBF1) and Tris[(9,9,9',9'-tetraoctyl-2,2'-bifluoren-7-yl)duryl]borane (DBF2), were designed and synthesized for use in solution-processed phosphorescent organic light-emitting diodes (OLEDs). These materials show good solubility and excellent thermal stability. The photophysical study revealed that there is no significant pi-conjugation between the tridurylborane core and the oligoflourene endcaps due to the strong steric hindrance of bulky duryl groups. DBF1 has sufficiently high triplet energy so as to act as host material for green phosphors. Green phosphorescent OLEDs were fabricated by partially solution-processing technique with DBF1 as host and traditional green iridium phosphor as doped emitter. An optimized device exhibited high efficiencies of 36.77 cd A(-1), 23.09 lm W-1 and 10.81%, which are close to the best data for partially solution-processed green phosphorescent OLEDs containing small molecular hosts reported so far. (C) 2012 Elsevier Ltd. All rights reserved.