We present the factors influencing the orientation of the phosphorescent dyes in phosphorescent OLEDs. And, we report that an OLED containing a phosphorescent emitter with horizontally oriented dipoles in an exciplex-forming co-host that exhibits an extremely high EQE of 32.3% and power efficiency of 142 lm/W, the highest values ever reported in literature. Furthermore, we experimentally and theoretically correlated the EQE of OLEDs to the PL quantum yield and the horizontal dipole ratio of phosphorescent dyes using three different dyes.

Date Published: 8 October 2014
PDF: 7 pages
Proc. SPIE 9183, Organic Light Emitting Materials and Devices XVIII, 918326 (8 October 2014); doi: 10.1117/12.2062527

Published in SPIE Proceedings Vol. 9183:
Organic Light Emitting Materials and Devices XVIII
Franky So; Chihaya Adachi, Editor(s)