High-Efficiency Phosphorescent Hybrid Organic-Inorganic Light-Emitting Diodes Using a Solution-Processed Small-Molecule Emissive Layer.
The morphology and optical and electrical properties of solution-processed and vacuum-deposited 4,4',4″-tris(carbazol-9-yl)triphenylamine (TCTA):2,2'-(1,3-phenylene)bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole] (OXD-7) composite films are investigated. All of the films exhibit smooth and pinhole-free morphology, while the evaporated films possess enhanced carrier-transport properties compared to solution-processed ones. The close correlation between the carrier-transport feature and the packing density of the film is established. High-efficiency monochromatic and white phosphorescent hybrid organic-inorganic light-emitting diodes with solution-processed small-molecule emissive layers are reported: the maximum external quantum efficiencies of blue, yellow, and red devices are 18.9, 14.6, and 10.2%, respectively; white devices show a maximum luminance efficiency of 40 cd A(-1) and a power efficiency of 20.8 lm W(-1) at 1000 cd m(-2). The efficiencies of blue, red, and white devices represent significant improvement over previously reported values.
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Changjun
C
Fan
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Yong
Y
Lei
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Zhen
Z
Liu
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Ruixue
R
Wang
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Yanlian
Y
Lei
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Guoqing
G
Li
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Zuhong
Z
Xiong
School of Physical Science and Technology, Southwest University , Chongqing 400715, P. R. China.
Xiaohui
X
Yang
carrier-transport property; hybrid organic−inorganic light-emitting diodes; packing density of the film; solution-processed small-molecule films; vacuum-deposited films