Thermally activated and aggregation-regulated excitonic coupling enable emissive high-lying triplet excitons
Date
08/08/2022Grant ID
101025143
EP/P010482/1
SRF\R1\201089
Keywords
Metadata
Show full item recordAbstract
Room-temperature phosphorescence (RTP) originating from higher-lying triplet excitons remains a rather rarely documented occurrence for purely organic molecular systems. Here, we report two naphthalene-based RTP luminophores whose phosphorescence emission is enabled by radiative decay of high-lying triplet excitons. In contrast, upon cooling the dominant phosphorescence originates from the lowest-lying triplet excited state, which is manifested by a red-shifted emission. Photophysical and theoretical studies reveal that the unusual RTP results from thermally activated excitonic coupling between different conformations of the compounds. Aggregation-regulated excitonic coupling is observed when increasing the doping concentration of the emitters in poly(methylmethacrylate) (PMMA). Further, the RTP quantum efficiency improves more than 80-fold in 1,3-bis(N-carbazolyl)benzene (mCP) compared to that in PMMA. This design principle offers important insight into triplet excited state dynamics and has been exploited in afterglow-indicating temperature sensing.
Citation
Wang , T , De , J , Wu , S , Gupta , A K & Zysman-Colman , E 2022 , ' Thermally activated and aggregation-regulated excitonic coupling enable emissive high-lying triplet excitons ' , Angewandte Chemie International Edition , vol. 61 , no. 33 , e202206681 . https://doi.org/10.1002/anie.202206681
Publication
Angewandte Chemie International Edition
Status
Peer reviewed
ISSN
1433-7851Type
Journal article
Description
Funding: Horizon 2020 Framework Programme (Grant Number(s): 897098; Grant recipient(s): Tao Wang, Eli Zysman-Colman); Horizon 2020 Framework Programme (Grant Number(s): 101025143; Grant recipient(s): Eli Zysman-Colman, Joydip De); Engineering and Physical Sciences Research Council (Grant Number(s): EP/P010482/1; Grant recipient(s): Eli Zysman-Colman); Royal Society (Grant Number(s): SRF\R1\201089; Grant recipient(s): Abhishek Kumar Gupta, Eli Zysman-Colman); China Scholarship Council (GrantNumber(s): 201906250199; Grant recipient(s): Sen Wu)Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.