Abstract
Most of the recent studies are mainly focused on the single-host OLEDs, where the host is only hole-or electron-transporting for inducing the imbalance injection of holes and electrons in the emissive layer, thus it has a detrimental effect on device efficiency. In this work, simple high efficient solution-processed organic light-emitting diodes are developed using red commercial phosphorescent material Ir (pq)2 (acac). This paper presents our effort on exploring mixed-host devices based on a hole-transporting host 4, 4', 4''-tris (N-carbazolyl)-triphenylamine (TCTA) blended with a bipolar host material 4, 4'-bis-(carbazol-9-yl) biphenyl (CBP). The emitting layer is spin-coated with doping Ir (pq)2 (acac) as the red emitter. The optimized PhOLEDs doped with 6 wt% of Ir (pq)2 (acac) shows a maximum luminance efficiency of 16.6 cd/A, it is 1.5 times than that of the device with CBP as the single host.
Original language | English |
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Pages (from-to) | 119-123 |
Number of pages | 5 |
Journal | Nanjing Youdian Daxue Xuebao (Ziran Kexue Ban)/Journal of Nanjing University of Posts and Telecommunications (Natural Science) |
Volume | 34 |
Issue number | 4 |
State | Published - 1 Aug 2014 |
Externally published | Yes |
Keywords
- Doping
- Mixed-host
- Organic light-emitting devices
- Red phosphorescence