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

Zhiyi Li; Ruifang Wang; Yangyang Zeng; Xiangyu Dong; Guanhao Liu; Xiaoxiao Hu; Teng Gao; Honglei Gao; Yuanyuan Qin; Xiuxian Gu; Chun-Sing Lee; Jiguang Liu; Pengfei Wang; Ying Wang

doi:10.1055/a-1711-5768

Organic Materials, Table of Contents

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

Authors

Zhiyi Li

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Ruifang Wang

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Yangyang Zeng

^cSchool of Materials Design & Engineering, Beijing Institute of Fashion Technology, Beijing 100029, P. R. of China
Xiangyu Dong

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Guanhao Liu

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Xiaoxiao Hu

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Teng Gao

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Honglei Gao

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Yuanyuan Qin

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Xiuxian Gu

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Chun-Sing Lee

^dCenter of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong SAR, P. R. of China
Jiguang Liu

^cSchool of Materials Design & Engineering, Beijing Institute of Fashion Technology, Beijing 100029, P. R. of China
Pengfei Wang

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China
Ying Wang

^aKey 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

^bUniversity of Chinese Academy of Sciences, Beijing 100049, P. R. of China

Abstract

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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.

Key words

OLED - fluorescence - TADF

Full Text

References

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Supplementary Material

Supporting Information for this article is available online. (PDF)