Open AccessDependence of Light‐Emitting Characteristics of Blue Phosphorescent Organic Light‐Emitting Diodes on Electron Injection and Transport Materials
Author(s) -
Lee JeongIk,
Lee Jonghee,
Lee JooWon,
Cho DooHee,
Shin JinWook,
Han JunHan,
Chu Hye Yong
Publication year - 2012
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.12.0112.0014
Subject(s) - phosphorescence , phosphorescent organic light emitting diode , oled , quantum efficiency , materials science , optoelectronics , diode , electron , doping , luminance , electron transport chain , photochemistry , layer (electronics) , chemistry , fluorescence , optics , physics , nanotechnology , quantum mechanics , biochemistry
We investigate the light‐emitting performances of blue phosphorescent organic light‐emitting diodes (PHOLEDs) with three different electron injection and transport materials, that is, bathocuproine(2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline) (Bphen), 1,3,5‐tri(m‐pyrid‐3‐yl‐phenyl)benzene (Tm3PyPB), and 2,6‐bis(3‐(carbazol‐9‐yl)phenyl)pyridine (26DCzPPy), which are partially doped with cesium metal. We find that the device characteristics are very dependent on the nature of the introduced electron injection layer (EIL) and electron transporting layer (ETL). When the appropriate EIL and ETL are combined, the peak external quantum efficiency and peak power efficiency improve up to 20.7% and 45.6 lm/W, respectively. Moreover, this blue PHOLED even maintains high external quantum efficiency of 19.6% and 16.9% at a luminance of 1,000 cd/m 2 and 10,000 cd/m 2 , respectively.