High-efficiency white organic light-emitting diodes using blue and red phosphorescent materials with exciton blocking layer.
High-efficiency white organic light-emitting diodes (WOLEDs) were fabricated with two emissive layers and an exciton blocking layer (EBL) was sandwiched between two phosphorescent dyes, bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium III (Flrpic) as the blue emission and iridium(III) bis(5-acetyl-2-phenylpyridinato-N,C2') acetylacetonate ((acppy)2Ir(acac)) as the red emission. This EBL effectively prevented a triple-triple energy transfer between the two phosphorescent emissive layers with blue and red emission. The white device showed Commission Internationale De L'Eclairage (CIE(x, y)) coordinates of (0.33, 0.42) at 22400 cd/m2, a maximum luminance of 27300 cd/m2 at 13.2 V, and a maximum luminous efficiency of 26.9 cd/A.
Park
Jung Hyun
JH
Department of Information Display, Hongik University, Seoul, 121-791, Korea.
Seo
Ji Hoon
JH
Seo
Ji Hyun
JH
Lee
Seok Jae
SJ
Koo
Ja Ryong
JR
Yoon
Seung Soo
SS
Lee
Seung Hee
SH
Kim
Young Kwan
YK