High Brightness White Organic Light Emitting Devices Employing Phosphorescent Iridium Complex as RGB Dopants

Abstract:

An efficient phosphorescent white organic light-emitting diode (WOLED) was realized by using a bright blue-emitting layer, iridium (III) bis [(4, 6-di-fluoropheny)-pyridinato-N, C2’] picolinate doped 4.4’-bis (9-carbazolyl)-2, 2’-dimethyl-biphenyl, together with tris (2- Phenylpyridine) iridium and bis (1-phenyl-isoquinoline) acetylacetonate iridium (III) were codoped into 4,4’-N,N’-dicarbazole-biphenyl layer to provide blue, green, and red emission for color mixing. The device emission color was controlled by varying dopant concentrations and the thickness of blue and green-red layers as well as tuning the thickness of exciton-blocking layer. The maximum luminance and power efficiency of the WOLED were 37100cd/m2 at 17 V and 7.37lm/W at 5V, respectively. The Commission Internationale de 1’Eclairage (CIE) chromaticity coordinate changes from (0.41, 0.42) to (0.37, 0.39) when the luminance rangeed from 1000cd/m2 to 30000cd/m2.

• Periodical: Key Engineering Materials (Volumes 364-366)
• Pages: 1072-1076
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.364-366.1072
• Online since: December 2007
• Authors: Rui Li Song, Yu Duan
• Keywords: Bright, Efficient, Iridiumd Phosphorescent Dopants, Stable CIE Coordinated, White Organic Light Emitting Device

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