Theoretical arrangement of thermally activated delayed fluorescence as host for fluorescent emitter with blue to red emission

Jianzhong Fan; Yuchen Zhang; Kai Zhang; Jie Liu; Guanyu Jiang; Feiyan Li; Lili Lin; Chuan-Kui Wang

doi:10.1016/j.saa.2019.04.033

Theoretical arrangement of thermally activated delayed fluorescence as host for fluorescent emitter with blue to red emission

Spectrochim Acta A Mol Biomol Spectrosc. 2019 Aug 5:219:44-52. doi: 10.1016/j.saa.2019.04.033. Epub 2019 Apr 17.

Authors

Jianzhong Fan¹, Yuchen Zhang¹, Kai Zhang¹, Jie Liu¹, Guanyu Jiang¹, Feiyan Li¹, Lili Lin², Chuan-Kui Wang³

Affiliations

¹ Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, 250014 Jinan, China.
² Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, 250014 Jinan, China. Electronic address: linll@sdnu.edu.cn.
³ Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, 250014 Jinan, China. Electronic address: ckwang@sdnu.edu.cn.

PMID: 31030046
DOI: 10.1016/j.saa.2019.04.033

Abstract

Thermally activated delayed fluorescence (TADF) emitter is applied to obtain high triplet exciton utilization through reverse intersystem crossing process. However, for efficient TADF emitter, the contradiction between high efficiency and utilization need to be carefully balanced. In this work, we provide a theoretical design strategy to realize high exciton utilization and high luminescence efficiency simultaneously by taking the TADF molecules as host and efficient fluorescent luminescence molecules as guest to form TADF-host:fluorescence-guest system. Through investigating the photophysical properties by optimal Hartree-Fock (OHF) method, different TADF-host and various fluorescence-guest schemes are arranged. Moreover, large overlap between the emission spectra of TADF-host and the absorption spectra of fluorescence-guest indicates efficient Förster energy transfer process. Thus, five systems with blue to red emission are obtained. Furthermore, the charge transfer properties are studied by Marcus equation, efficient charge mobility and balanced charge transfer can be expected for studied systems which are important in constructing organic light emitting diodes (OLEDs). This work could provide promising emitting layer architecture for OLEDs with ultimate performance.

Keywords: Blue emission; Optimal Hartree-Fock method; Organic light emitting diodes; Thermally activated delayed fluorescence.