skip to main content

DOE PAGESDOE PAGES

Title: Hot excited state management for long-lived blue phosphorescent organic light-emitting diodes

Since their introduction over 15 years ago, the operational lifetime of blue phosphorescent organic light-emitting diodes (PHOLEDs) has remained insufficient for their practical use in displays and lighting. Their short lifetime results from annihilation between high-energy excited states, producing energetically hot states (46.0 eV) that lead to molecular dissociation. We introduce a strategy to avoid dissociative reactions by including a molecular hot excited state manager within the device emission layer. Hot excited states transfer to the manager and rapidly thermalize before damage is induced on the dopant or host. As a consequence, the managed blue PHOLED attains T80=334±5 h (time to 80% of the 1,000 cd m -2 initial luminance) with a chromaticity coordinate of (0.16, 0.31), corresponding to 3.6±0.1 times improvement in a lifetime compared to conventional, unmanaged devices. We believe that, this significant improvement results in the longest lifetime for such a blue PHOLED.
Authors:
 [1] ;  [1] ;  [2] ;  [3] ;  [2] ;  [4]
  1. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Electrical and Computer Engineering
  2. Univ. of Southern California, Los Angeles, CA (United States). Dept. of Chemistry
  3. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Physics
  4. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Electrical and Computer Engineering, Dept. of Physics, Dept. of Materials Science and Engineering
Publication Date:
Grant/Contract Number:
EE0007077
Type:
Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Research Org:
Univ. of Michigan, Ann Arbor, MI (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; electronic devices; engineering
OSTI Identifier:
1389266