Studies of fluorescence/phosphorescence hybrid white organic light-emitting diodes

Abstract

White organic light-emitting diodes (WOLEDs) have attracted more and more attention due to their wide applications in full-color displays, solid-state lighting sources and backlight sources. Amongst, fluorescence/hosphorescence hybrid WOLEDs are considered as promising device structures in lighting application because of the long lifetime of fluorescence materials and the high efficiency of phosphorescence materials. For fluorescence/hosphorescence hybrid WOLEDs, it is very important to resolve the synergic emission from the singlet excitons of fluorescence materials to the triplet excitons of phosphorescence materials. The design of effective device structures is necessary to avoid the quench between the singlet excitons and triplet excitons. In this paper, we introduced the structure design and performances of fluorescence/phosphorescence hybrid WOLEDs with different structures based on two blue fluorescence materials with different triplet levels. It is experimentally demonstrated that the high effective structure design with charge carrier transport balance and the effective control of exciton distribution in a wide range are keys in realizing high performance fluorescence/phosphorescence hybrid WOLEDs.