CC BY-NC-ND 4.0 · Organic Materials 2021; 3(04): 488-492
DOI: 10.1055/a-1711-5768
Organic Materials in Electronics
Short Communication

Sensitized Fluorescence Organic Light-Emitting Diodes with Reduced Efficiency Roll-Off

a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Ruifang Wang
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Yangyang Zeng
c   School of Materials Design & Engineering, Beijing Institute of Fashion Technology, Beijing 100029, P. R. of China
,
Xiangyu Dong
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Guanhao Liu
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Xiaoxiao Hu
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Teng Gao
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Honglei Gao
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Yuanyuan Qin
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Xiuxian Gu
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
d   Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong SAR, P. R. of China
,
Jiguang Liu
c   School of Materials Design & Engineering, Beijing Institute of Fashion Technology, Beijing 100029, P. R. of China
,
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
a   Key Laboratory of Photochemical Conversion and Optoelectronic Materials and CityU−CAS Joint Laboratory of Functional Materials and Devices, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. of China
b   University of Chinese Academy of Sciences, Beijing 100049, P. R. of China
› Author Affiliations


Abstract

Thermally activated delayed fluorescence (TADF)-sensitized fluorescence is a promising strategy to maintain the advantage of TADF materials and fluorescent materials. Nevertheless, the delayed lifetime of the TADF sensitizer is still relatively long, which causes heavy efficiency roll-off. Here we reported a valid tactic to construct fluorescent devices with low-efficiency roll-off by utilizing the TADF sensitizer with a reduced delayed lifetime. By the construction of the sensitization system, the energy transfer efficiency can reach up to 90%. The high-energy transfer efficiency and the TADFʼs short delayed lifetime result in high sensitization over 95% and the maximum external quantum efficiency of 16.2%. Meanwhile, the TADF-sensitized fluorescent devices exhibit reduced efficiency roll-off with an “onset” current density of 23 mA · cm−2. Our results provide an effective strategy to reduce the efficiency roll-off of the TADF sensitization system.



Publication History

Received: 11 October 2021

Accepted: 17 November 2021

Accepted Manuscript online:
02 December 2021

Article published online:
27 December 2021

© 2021. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
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