Enhanced electrophosphorescence of copper complex based devices by codoping an iridium complex

• Published in: Applied physics letters Vol. 90; no. 14; pp. 143505 - 143505-3
• Main Authors: Su, Zisheng, Li, Wenlian, Che, Guangbo, Xu, Maoliang, Kong, Zhiguo, Wang, Dan, Xin, Qi, Han, Liangliang, Chu, Bei, Bi, Defeng
• Format: Journal Article
• Language: English
• Published: American Institute of Physics 02-04-2007
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.2719238

Evidently enhanced electrophosphorescence of [Cu(bis[2-(diphenylphosphino)phenyl] ether)(6,7-dicyanodipyrido
[
2
,
2
-
d
:
2
′
,
3
′
-
f
]
quinoxaline)]
B
F
4
(
Cu
I
complex) by codoping bis[(4,6-difluorophenyl)-pyridinato-N,
C
2
](picolinato)Ir(III) (FIrpic) into the same host,
4
,
4
′
-
N
,
N
′
-dicarbazole-biphenyl, was demonstrated. The device codoped with
8
wt
%
FIrpic and
2
wt
%
Cu
I
complex shows a maximum current efficiency and power efficiency of
26.6
cd
∕
A
and
17.8
lm
∕
W
, respectively, which were increased by factors of 2.6 and 2.1 compared with the
2
wt
%
Cu
I
complex monodoped device. The improvements of the devices were testified to the
efficient energy transfer from FIrpic to the
Cu
I
complex. The detail of the energy transfer
mechanism between the two phosphors was also proposed.