A dicarbazole-triazine hybrid bipolar host material for highly efficient green phosphorescent OLEDs

Chih Hao Chang, Ming Cheng Kuo, Wei Chieh Lin, Yu Ting Chen, Ken Tsung Wong, Shu Hua Chou, Ejabul Mondal, Raymond C. Kwong, Sean Xia, Tetsuya Nakagawa, Chihaya Adachi

Research output: Contribution to journalArticlepeer-review

104 Citations (Scopus)

Abstract

A novel bipolar host material 9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9′- phenyl-3,3′-bicarbazole (CzT) comprising a dicarbazole donor linking to an electron deficient 1,3,5-triazine acceptor was synthesized and characterized. The molecular design of CzT allows the spatial separation of HOMO and LUMO on the donor and acceptor moieties, respectively, giving sufficient triplet energy (2.67 eV) together with promising physical properties and morphological stability (T g = 134°C). This tailor-made material was used as a host for an efficient yellowish-green iridium complex, bis(o-tolylpyrimidinato- N,C 2′)Ir(iii)acetylacetonate [(TPm) 2Ir(acac)]; the as-fabricated phosphorescent OLEDs (PHOLEDs) demonstrated high performance, with maximum efficiencies of 20.0% (75.7 cd A -1 and 71.3 lm W -1) and 20.1% (76.3 cd A -1 and 72.7 lm W -1) achieved in trilayer and bilayer device architectures, respectively. The efficiency of the trilayer device can sustain ∼20% over a wide brightness range from 10 2 to 10 3 cd m -2 due to the more effective confinement of emissive excitons within the emitting layer.

Original languageEnglish
Pages (from-to)3832-3838
Number of pages7
JournalJournal of Materials Chemistry
Volume22
Issue number9
DOIs
Publication statusPublished - Mar 7 2012

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Chemistry

Fingerprint

Dive into the research topics of 'A dicarbazole-triazine hybrid bipolar host material for highly efficient green phosphorescent OLEDs'. Together they form a unique fingerprint.

Cite this