N-heterocyclic carbazole-based hosts for simplified single-layer phosphorescent OLEDs with high efficiencies.

Hudson, Zachary M; Wang, Zhibin; Helander, Michael G; Lu, Zheng-Hong; Wang, Suning · Adv Mater · 2012

basic_science · Level V

Where this comes from

Abstract

Highly efficient single-layer organic light-emitting diodes (OLEDs) are demonstrated using new N-heterocyclic carbazole-based host materials. Phosphorescent OLEDs with a structure of ITO/MoO(3) /host/host:dopant/host/Cs(2) CO(3) /Al are fabricated in which the new materials act simultaneously as electron-transport, hole-transport, and host layer. Devices with maximum current and external quantum efficiencies of 92.2 cd A(-1) and 26.8% are achieved, the highest reported to date for a single-layer OLED.

Medical subject headings