ZHU Ying-guang, LIANG Chun-jun, LIU Shu etc. Effect of Interlayer on Phosphorescent White Organic Light-emitting Diodes[J]. Chinese Journal of Luminescence, 2014,35(7): 824-829
ZHU Ying-guang, LIANG Chun-jun, LIU Shu etc. Effect of Interlayer on Phosphorescent White Organic Light-emitting Diodes[J]. Chinese Journal of Luminescence, 2014,35(7): 824-829 DOI: 10.3788/fgxb20143507.0824.
Effect of Interlayer on Phosphorescent White Organic Light-emitting Diodes
Phosphorescent white organic light-emitting diodes with double light-emitting layers were fabricated based on phosphorescent blue emittor bis [3
5-difluoro-2-(2-pridyl)phenyl-(2-earboxypyribyl)iridumⅢ] (FIrpic) and red emittor bis(2-methyldibenzo[f
h]
quinoxaline)(acetylacetonate) iridium(Ⅲ)(Ir(MDQ)
2
acac). FIrpic was doped in an ultra wide band-gap host 1
3-bis(triphenylsilyl)benzene (UGH3)
and Ir(MDQ)
2
acac was doped in the host 4
4'
4"-tris(carbazol-9-yl)triphenylamine(TCTA). A hole transporting wide-band-gap material 1
3-bis(carbazol-9-yl)benzene (mCP) was introduced between the emitting layers. The device structure was ITO/NPB(40 nm)/TCTA:Ir(MDQ)
2
acac 7%(10 nm)/mCP(
x
nm)/UGH3:Firpic 8%(30 nm)/BPhen(30 nm)/LiF(0.8 nm)/Al(200 nm). The results show that the interlayer plays an important role of balancing charge carriers
and blocking energy transfer between the emitting layers. With an appropriate thickness of the interlayer
the device performances can be significantly enhanced. Compared with the device without interlayer
the maximum current efficiency can be enhanced from 3.4 cd/A to 13.2 cd/A.
关键词
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references
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