White Polymer Light-Emitting Diodes Based on Exciplex Electroluminescence from Polymer Blends and a Single Polymer

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

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Author(s)

  • Junfei Liang
  • Sen Zhao
  • Xiao-Fang Jiang
  • Ting Guo
  • Lei Ying
  • Fei Huang
  • Wei Yang
  • Yong Cao

Detail(s)

Original languageEnglish
Pages (from-to)6164-6173
Journal / PublicationACS Applied Materials and Interfaces
Volume8
Issue number9
Publication statusPublished - 9 Mar 2016
Externally publishedYes

Abstract

In this Article, we designed and synthesized a series of polyfluorene derivatives, which consist of the electron-rich 4,4′-(9-alkyl-carbazole-3,6-diyl)bis(N,N-diphenylaniline) (TPA-Cz) in the side chain and the electron-deficient dibenzothiophene-5,5-dioxide (SO) unit in the main chain. The resulting copolymer PF-T25 that did not comprise the SO unit exhibited blue light-emission with the Commission Internationale de L'Eclairage coordinates of (0.16, 0.10). However, by physically blending PF-T25 with a blue light-emitting SO-based oligomer, a novel low-energy emission correlated to exciplex emerged due to the appropriate energy level alignment of TPA-Cz and the SO-based oligomers, which showed extended exciton lifetime as confirmed by time-resolved photoluminescent spectroscopy. The low-energy emission was also identified in copolymers consisting of SO unit in the main chain, which can effectively compensate for the high-energy emission to produce binary white light-emission. Polymer light-emitting diodes based on the exciplex-type single greenish-white polymer exhibit the peak luminous efficiency of 2.34 cd A-1 and the maximum brightness of 12 410 cd m-2, with Commission Internationale de L'Eclairage color coordinates (0.27, 0.39). The device based on such polymer showed much better electroluminescent stability than those based on blending films. These observations indicated that developing a single polymer with the generated exciplex emission can be a novel and effective molecular design strategy toward highly stable and efficient white polymer light-emitting diodes.

Research Area(s)

  • exciplex, highly stable electroluminescence, polymer light-emitting diodes, solution process, white light-emitting

Bibliographic Note

Publication details (e.g. title, author(s), publication statuses and dates) are captured on an “AS IS” and “AS AVAILABLE” basis at the time of record harvesting from the data source. Suggestions for further amendments or supplementary information can be sent to [email protected].

Citation Format(s)

White Polymer Light-Emitting Diodes Based on Exciplex Electroluminescence from Polymer Blends and a Single Polymer. / Liang, Junfei; Zhao, Sen; Jiang, Xiao-Fang et al.
In: ACS Applied Materials and Interfaces, Vol. 8, No. 9, 09.03.2016, p. 6164-6173.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review