Issue 42, 2017

Engineering the excited-state properties of purely organic intramolecular and intermolecular charge transfer emitters towards high-performance fluorescent OLEDs

Abstract

A direct comparative investigation on the electrofluorescence performances of pure-organic intramolecular charge transfer (ICT) and intermolecular charge transfer (inter-CT) materials, which have high correlation in their molecular structures, was carried out. An n-type spiro-sulfone-based acceptor (DSO2) with a sufficiently large molecular weight is developed to serve as the acceptor in both ICT and inter-CT systems. Through manipulating their excited-state properties by molecular engineering, transformation of conventional fluorescence and thermally activated delayed fluorescence (TADF) from both the inter-CT and ICT systems could be rationally modulated. Accordingly, a conventional fluorescent, non-doped, blue OLED with an external quantum efficiency (EQE) >6.0% at a luminance of 1000 cd m−2 and a low turn-on voltage (Von) of 2.76 V was obtained; maximum EQEs of 18.2% and 25.4% were achieved for the non-doped and doped sky-blue OLEDs employing an ICT emitter with a TADF character, respectively. Besides, an OLED using the inter-CT emitter could also show good device performance with an EQE of up to 10.2%. This study contributes to understanding how to develop high-performance ICT and inter-CT emitters with selective thermally activated delayed and conventional electrofluorescence through excited-state modulation.

Graphical abstract: Engineering the excited-state properties of purely organic intramolecular and intermolecular charge transfer emitters towards high-performance fluorescent OLEDs

Supplementary files

Article information

Article type
Paper
Submitted
02 sep 2017
Accepted
29 sep 2017
First published
29 sep 2017

J. Mater. Chem. C, 2017,5, 10991-11000

Engineering the excited-state properties of purely organic intramolecular and intermolecular charge transfer emitters towards high-performance fluorescent OLEDs

D. Chen, K. Liu, X. Li, B. Li, M. Liu, X. Cai, Y. Ma, Y. Cao and S. Su, J. Mater. Chem. C, 2017, 5, 10991 DOI: 10.1039/C7TC04014H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements