Harvesting Triplet Excitons in High Mobility Emissive Organic Semiconductor for Efficiency Enhancement of Light-Emitting Transistors

Can Gao; Atul Shukla; Haikuo Gao; Zhagen Miao; Yihan Zhang; Pu Wang; Guiwen Luo; Yi Zeng; Wallace W H Wong; Trevor A Smith; Shih-Chun Lo; Wenping Hu; Ebinazar B Namdas; Huanli Dong

doi:10.1002/adma.202208389

Harvesting Triplet Excitons in High Mobility Emissive Organic Semiconductor for Efficiency Enhancement of Light-Emitting Transistors

Adv Mater. 2023 Mar;35(13):e2208389. doi: 10.1002/adma.202208389. Epub 2023 Feb 13.

Authors

Can Gao¹, Atul Shukla², Haikuo Gao³, Zhagen Miao^{1

4}, Yihan Zhang^{1

4}, Pu Wang^{1

4}, Guiwen Luo^{4

5}, Yi Zeng⁵, Wallace W H Wong⁶, Trevor A Smith⁷, Shih-Chun Lo⁸, Wenping Hu⁹, Ebinazar B Namdas², Huanli Dong¹

Affiliations

¹ Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
² Centre for Organic Photonics & Electronics, School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, 4072, Australia.
³ Shandong Engineering Research Center of Aeronautical Materials and Devices, College of Aeronautical Engineering, Binzhou University, Binzhou, 251900, China.
⁴ School of Chemical Science, University of Chinese Academy of Sciences, Beijing, 100049, China.
⁵ Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
⁶ ARC Centre of Excellence in Exciton Science, School of Chemistry, Bio21 Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia.
⁷ ARC Centre of Excellence in Exciton Science, School of Chemistry, The University of Melbourne, Melbourne, VIC, 3010, Australia.
⁸ Centre for Organic Photonics and Electronics, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
⁹ Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China.

PMID: 36639351
DOI: 10.1002/adma.202208389

Abstract

Organic light-emitting transistors (OLETs), a kind of highly integrated and minimized optoelectronic device, demonstrate great potential applications in various fields. The construction of high-performance OLETs requires the integration of high charge carrier mobility, strong emission, and high triplet exciton utilization efficiency in the active layer. However, it remains a significant long-term challenge, especially for single component active layer OLETs. Herein, the successful harvesting of triplet excitons in a high mobility emissive molecule, 2,6-diphenylanthracene (DPA), through the triplet-triplet annihilation process is demonstrated. By incorporating a highly emissive guest into the DPA host system, an obvious increase in photoluminescence efficiency along with exciton utilization efficiency results in an obvious enhancement of external quantum efficiency of 7.2 times for OLETs compared to the non-doped devices. Moreover, well-tunable multi-color electroluminescence, especially white emission with Commission Internationale del'Eclairage of (0.31, 0.35), from OLETs is also achieved by modulating the doping concentration with a controlled energy transfer process. This work opens a new avenue for integrating strong emission and efficient exciton utilization in high-mobility organic semiconductors for high-performance OLETs and advancing their related functional device applications.

Keywords: harvesting triplet excitons; high efficiency; high mobility; organic light-emitting transistors; organic semiconductors; strong emission; tunable emission colors.

Abstract

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