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http://dx.doi.org/10.14478/ace.2015.1108

Efficient Green Phosphorescent OLEDs with Hexaazatrinaphthylene Derivatives as a Hole Injection Layer  

Lee, Jae-Hyun (Department of Creative Convergence Engineering, Hanbat National University)
Lee, Jonghee (OLED Research Center, Electronics and Telecommunications Research Institute)
Publication Information
Applied Chemistry for Engineering / v.26, no.6, 2015 , pp. 725-729 More about this Journal
Abstract
Organic light emitting diodes (OLEDs) are regarded as the next generation display and solid-state lighting due to their superb achievements from extensive research efforts on improving the efficiency and stability of OLEDs in addition to developing new materials. Herein, efficient green phosphorescent OLEDs were obtained by using hexaazatrinaphthylene (HAT) derivatives as a hole injection layer. External quantum and current efficiencies of OLEDs were enhanced from 8.8% and 30.8 cd/A to 13.6% and 47.7 cd/A, respectively by inserting a thin layer of HAT derivatives between the ITO and hole transporting layer. The enhancement of OLEDs was found to be originated from the inserted HAT derivatives, which resulted in the optimized hole-electron balance inside the emission layer.
Keywords
organic light emitting diodes; hole injection layer; efficiency;
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