The quest for high-performance host materials for electrophosphorescent blue dopants
Journal
Advanced Functional Materials
Journal Volume
17
Journal Issue
12
Pages
1887-1895
Date Issued
2007
Author(s)
Abstract
We report a systematic comparison study of 3,5-di(N-carbazolyl) tetraphenylsilane (SimCP) and N,N′-dicarbazolyl-3,5-benzene (mCP), which are used as the host materials for phosphorescent blue dopants in organic light-emitting diodes (OLEDs). On the basis of photoexcitation emission spectroscopy, thermal stability analysis, photoelectron analysis, charge transport measurements, and molecular dynamics (MD) simulations, we conclude that the non-π-conjugated meta-substituted triphenylsilyl moiety of SimCP exerts a unique hindering effect on the molecular packing characteristics in the condensed phase. The chemical origin of the superior performance of SimCP over mCP is revealed, and is expected to be helpful for the molecular design of effective host materials for enhancing the performance of blue phosphorescent OLEDs. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.
Publisher
John Wiley & Sons, Inc.
Type
journal article