An organic electroluminescent compound containing Iridium, preparation method thereof and an organic electroluminescent device are disclosed. The compound is represented by the structure (2), wherein, R is C1˜C4 alkyl. The structure of the compound contains bipyridine ligand, also carries alkoxy group and fluorine atom, which improves its carrier injection and transfer ability, and increases its internal quantum efficiency and electroluminescent efficiency. Furthermore, the compound uses strong field ligand 2-pyridine carboxylic acid as assistant ligand, which causes an effective blue shift of its emission spectrum and increases light-emitting efficiency of blue light phosphorescence greatly.
Deep-blue phosphorescent iridium(III) dyes based on fluorine-functionalized bis(2,3′-bipyridyl) ligand for efficient organic light-emitting diodes
作者:Jieun Lee、Hyungkeun Park、Ki-Min Park、Jinho Kim、Jun-Yeob Lee、Youngjin Kang
DOI:10.1016/j.dyepig.2015.08.008
日期:2015.12
Four blue phosphorescent complexes with the general formula (4-R-dfpypy)2Ir(L<^>X), where 4-Rdfpypy 4-alkyl-2',6'-difluoro-2,3'-bipyridine and L<^>X = picolinate or dipivaloylmethanate, were synthesized, and their photoluminescent properties were systematically investigated. All complexes show bright deep-blue phosphorescence emissions with lambda(max) = 440-450 nm and quantum efficiencies of 0.25 - 0.78 in the fluid state. The emission bands of compounds 1-4 are slightly red shifted by 5-10 nm relative to the homoleptic congener, Ir(dfpypy)3. Electroluminescent (EL) devices were fabricated using compound 2 as a dopant, 1,3-bis(N-carbazolyl)benzene (mCP) as the host, and TSPO1 (diphenylphosphineoxide-4-(triphenylsilyl)phenyl) as the electron transporting/exciton blocking layer. These EL devices show a deep-blue color (CIE: x, y = 0.14, 0.17) with high efficiencies. The EL device of compound 2 at a doping level of 5 wt% has the best performance with an EQE of 14.6% at a brightness of 100 cd/m(2) and a current efficiency of 18.3 cd/A. (C) 2015 Elsevier Ltd. All rights reserved.
An organic electroluminescent compound containing Iridium, preparation method thereof and an organic electroluminescent device are disclosed. The compound is represented by the structure (2), wherein, R is C
1
˜C
4
alkyl. The structure of the compound contains bipyridine ligand, also carries alkoxy group and fluorine atom, which improves its carrier injection and transfer ability, and increases its internal quantum efficiency and electroluminescent efficiency. Furthermore, the compound uses strong field ligand 2-pyridine carboxylic acid as assistant ligand, which causes an effective blue shift of its emission spectrum and increases light-emitting efficiency of blue light phosphorescence greatly.