Hybrid Host Materials For Electrophosphorescent Devices
申请人:Chen Shaw H.
公开号:US20100184942A1
公开(公告)日:2010-07-22
Compounds (including polymers) for use in hybrid host materials which can be used in electroluminescent devices. The compounds comprise at least one electron-transporting moiety and at least one hole-transporting moiety which are joined by a flexible linker. Hybrid host materials comprising the compounds exhibit stability against phase separation, elevated glass transition temperature, morphological stability against crystallization, and isolation of the electron transporting moiety and hole transporting moiety π-systems.
Hybrid host materials for electrophosphorescent devices
申请人:Chen Shaw H.
公开号:US09040718B2
公开(公告)日:2015-05-26
Compounds (including polymers) for use in hybrid host materials which can be used in electroluminescent devices. The compounds comprise at least one electron-transporting moiety and at least one hole-transporting moiety which are joined by a flexible linker. Hybrid host materials comprising the compounds exhibit stability against phase separation, elevated glass transition temperature, morphological stability against crystallization, and isolation of the electron transporting moiety and hole transporting moiety π-systems.
A new class of non-conjugated bipolar hybrid hosts for phosphorescent organic light-emitting diodes
作者:Lichang Zeng、Thomas Y.-H. Lee、Paul B. Merkel、Shaw H. Chen
DOI:10.1039/b909787b
日期:——
Comprising hole- and electron-transporting moieties with flexible linkages, representative non-conjugated bipolar hybrids have been synthesized and characterized for a demonstration of their potential use as host materials for the fabrication of phosphorescent organic light-emitting diodes. The advantages of this material class include solution processing into amorphous films with elevated glass transition temperatures, stability against phase separation and crystallization, and provision of LUMO/HOMO levels and triplet energies contributed by the two independent moieties without constraint by the electrochemical energy gap. While exciplex formation between the hole- and electron-transporting moieties is inevitable, its adverse effects on spectral purity and device efficiency can be avoided by trapping charges on triplet emitters, as demonstrated for Ir(mppy)3 in TRZ-3Cz(MP)2, and TRZ-1Cz(MP)2. With these two bipolar hybrids and hole-transporting Cz(MP)2 as the host, the maximum current efficiency of the bilayer PhOLED is achieved with TRZ-3Cz(MP)2, but the driving voltage decreases monotonically with an increasing TRZ content.