Novel Carbazole/Fluorene Hybrids:  Host Materials for Blue Phosphorescent OLEDs

Abstract

[reaction: see text] A series of carbazole/fluorene (CBZm-Fn) hybrids were effectively synthesized through Friedel-Crafts-type substitution of the carbazole rings. These compounds were thermally and morphologically stable host materials for OLED applications. Efficient blue phosphorescent OLEDs were obtained when employing CBZ1-F2 as the host and FIrpic as the guest.

A morphologically stable host material for efficient phosphorescent green and red organic light emitting devices

“…Several studies have indicated that the thermal and morphological instabilities of host materials may shorten the operational lifetime of devices [14]. Therefore, various studies have been focused on hybridizing carbazole moiety with some bulky and steric groups, like triphenylsilane [15], fluorene [16], or tert-butyl benzene [17,18], to improve the thermal and morphological stability of the carbazolebased host materials and applied in electrophosphorescent OLEDs.…”

Molecular hosts for triplet emitters in organic light-emitting diodes and the corresponding working principle

“…Compared to DFC (17), a very structurally similar material 9-phenyl-3,6-bis(9-phenyl-9H-fluren-9-yl)-9H-carbazole (CBZ1-F2 (18)) has been developed by another research group (see Figure 7) [74]. FIrpic (2) and CBZ1-F2 (18) based device yielded efficiencies of 10.2% and 19.2 cd/A.…”

Fluoranthene-Based Molecules as Electron Transport and Blue Fluorescent Materials for Organic Light-Emitting Diodes

“…[8][9] In particular, the attainment of stable blue EL with high efficiency, good color purity and stability remains a challenge in both fluorescent and phosphorescent materials. [10][11][12] In an attempt to circumvent these issues, various π-conjugated organic materials such as anthracene, [13][14][15] pyrene, [16][17][18] fluorene, [19][20][21] and di(styryl)arylene [22][23] derivatives have been explored as a blue emitter for improving the efficiency and stability of OLEDs. All of these fluorophores show very high emission (nearly unity) in a dilute solution but suffer from concentration quenching in solid state due to molecular aggregation.…”