A Streamlined Steric-Shielding Approach Toward Efficient Narrowband (FWHM ~ 18 nm) Ultra-Violet Emitters for OLEDs

Abstract

Herein, a simple, yet verstitle molcular design was unraveled to develop a narrowband ultraviolet (UV) emitter by strategically integrating indolo[3,2,1-jk]carbazole and carbazole through a non-conjugative mode. The compound exhibited pure UV emission (λem~380 nm) with narrow FWHM of 18 nm. When utilized as emitter in OLEDs, it exhibited maximum EQE of 3.5% and CIEy of 0.037. As a host for green phosphorescent OLED, it demonstrated EQE of 22.9% with impressive low roll-off of 4% at 3000 cd/m2.