Elucidation of an aggregate excited state in the electrochemiluminescence and chemiluminescence of a thermally activated delayed fluorescence (TADF) emitter
Abstract
The electrochemistry, electrochemiluminescence (ECL), and chemiluminescence (CL) properties of a thermally activated delayed fluorescence (TADF) emitter 4,4′-(1,2-dihydroacenaphthylene-5,6-diyl)bis(N,N-diphenylaniline) (TPA-ace-TRZ) and three of its analogues were investigated. TPA-ace-TRZ exhibits both (a) delayed onset of ECL and (b) long-persistent luminescence, which we have attributed to the formation of an aggregate excited state in excimer or exciplex form. The evidence of this aggregate excited state was consistent across ECL annihilation and coreactant pathways as well as in CL. The absolute ECL efficiency of TPA-ace-TRZ using benzoyl peroxide (BPO) as a coreactant was found to be 0.028%, which was 9-fold stronger than the [Ru(bpy)3]2+/BPO reference coereactant system. Furthermore, the absolute CL quantum efficiency of TPA-ace-TRZ was determined to be 0.92%. The performance and flexibility of the TADF emitter TPA-ace-TRZ under these various emissive pathways are highly desirable toward applications in sensing, imaging, and light-emitting devices.
Citation
Chu , K , Adsetts , J R , Whitworth , Z , Kumar , S , Zysman-Colman , E & Ding , Z 2023 , ' Elucidation of an aggregate excited state in the electrochemiluminescence and chemiluminescence of a thermally activated delayed fluorescence (TADF) emitter ' , Langmuir , vol. 39 , no. 7 , pp. 2829-2837 . https://doi.org/10.1021/acs.langmuir.2c03391
Publication
Langmuir
Status
Peer reviewed
ISSN
0743-7463Type
Journal article
Rights
Copyright © 2023 American Chemical Society. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Description
Funding: Natural Sciences and Engineering Research Council Canada (NSERC, DG RGPIN-2018-06556 and SPG STPGP2016-493924), Canada Foundation of Innovation/Ontario Innovation Trust (CFI/OIT, 9040), and The University of Western Ontario. The authors acknowledge financial support from the European Union’s Horizon 2020 research and innovation program under a Marie Skłodowska Curie Individual Fellowship to S.K. (MCIF; agreement no. 748430-THF-OLED).Collections
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