Blue thermally activated delayed fluorescence emitter using modulated triazines as electron acceptors

November 13, 2019

Title

Blue thermally activated delayed fluorescence emitter using modulated triazines as electron acceptors

Author

Youngnam Lee, Seung-Je Woo, Jang-Joo Kim, Jong-In Hong

Year

2020

Journal

Dyes and Pigments

Abstract

Three types of thermally activated delayed fluorescence (TADF) emitters, namely, moTrSAc, tmTrSAc, and motmTrSAc, are reported that emit blue-shifted emission with high external quantum efficiencies (EQEs). These emitters have electron donating spiroacridine in common and various triazine-based electron acceptors. The electronic and structural control on the electron acceptor moiety adjusts the reduction potential of the molecule to shift the emission wavelength to the blue region. Moreover, as these emitters become widened, the light out-coupling efficiency increases due to the enhanced horizontal emitting dipole orientation. As a result, OLEDs based on moTrSAc, tmTrSAc, and motmTrSAc emit blue light in a range of 460–480 nm with high EQEs of 21.3, 15.5, and 19.5%, respectively.

Instrument

V-730, FP-8300

Keywords

Absoprtion, Fluorescence, Photoluminescence, Chemical stability, Materials