Premium
Self‐Organized Gradient Hole Injection to Improve the Performance of Polymer Electroluminescent Devices
Author(s) -
Lee T.W.,
Chung Y.,
Kwon O.,
Park J.J.
Publication year - 2007
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.200600278
Subject(s) - materials science , electroluminescence , oled , layer (electronics) , polymer , optoelectronics , common emitter , coating , ionomer , light emitting diode , styrene , diode , sulfonate , nanotechnology , copolymer , composite material , sodium , metallurgy
A new approach to forming a gradient hole‐injection layer in polymer light‐emitting diodes (PLEDs) is demonstrated. Single spin‐coating of hole‐injecting conducting polymer compositions with a perfluorinated ionomer results in a work function gradient through the layer formed by self‐organization, which leads to remarkably efficient single‐layer PLEDs (ca. 21 cd A –1 ). The device lifetime is significantly improved (ca. 50 times) compared with the conventional hole‐injection layer, poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonate). These results are a good example for demonstrating that the shorter lifetime of PLEDs compared with small‐molecule‐based organic LEDs (SM‐OLEDs) is not mainly due to the inherent degradation of the polymeric emitter itself. Hence, the results open the way to further improvements of PLEDs for real applications to large‐area, high‐resolution, and full‐color flexible displays.