Journal ArticleDOI
Luminescence, Stability, and Proton Response of an Open‐Shell (3,5‐Dichloro‐4‐pyridyl)bis(2,4,6‐trichlorophenyl)methyl Radical
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TLDR
A luminescent open-shell organic radical with high chemical stability was synthesized and the pyridine moiety acts as a proton coordination site, thereby allowing for control of the electronic and optical properties of the radical by protonation and deprotonation.Abstract:
A luminescent open-shell organic radical with high chemical stability was synthesized. (3,5-Dichloro-4-pyridyl)bis(2,4,6-trichlorophenyl)methyl radical (PyBTM) was photoluminescent under various conditions. Fluorescence quantum yields of 0.03, 0.26, and 0.81 (the highest value reported for a stable organic radical) were obtained in chloroform, in poly(methyl methacrylate) film at room temperature, and in an EPA matrix (diethyl ether:isopentane:ethanol) at 77 K, respectively. The photostability of PyBTM is up to 115 times higher than that of the tris(2,4,6-trichlorophenyl)methyl radical, a previously reported luminescent radical. The pyridine moiety of PyBTM acts as a proton coordination site, thereby allowing for control of the electronic and optical properties of the radical by protonation and deprotonation.read more
Citations
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Journal ArticleDOI
Efficient radical-based light-emitting diodes with doublet emission
Xin Ai,Emrys W. Evans,Shengzhi Dong,Alexander J. Gillett,Haoqing Guo,Yingxin Chen,Timothy J. H. Hele,Richard H. Friend,Feng Li,Feng Li +9 more
TL;DR: Efficient action is demonstrated of radical-based OLEDs16, whose emission originates from a spin doublet, rather than a singlet or triplet exciton, whose efficiency limitations imposed by tripleT excitons are circumvented for doublets.
Journal ArticleDOI
Organic Light‐Emitting Diodes Using a Neutral π Radical as Emitter: The Emission from a Doublet
TL;DR: The results pave a new way to obtain 100% internal quantum efficiency of OLEDs, in which an organic open-shell molecule, (4-N-carbazolyl-2,6-dichlorophenyl)bis(2,4-6-trichlor phenyl)methyl (TTM-1Cz) radical, is used as an emitter, to circumvent the transition problem of triplet.
Journal ArticleDOI
Recent advances in organic light-emitting diodes: toward smart lighting and displays
TL;DR: In this paper, a review of light emission mechanisms of electroluminescent materials is presented, and a brief perspective on future research is also proposed for pursuing the commercialization of OLEDs.
Journal ArticleDOI
High stability and luminescence efficiency in donor–acceptor neutral radicals not following the Aufbau principle
Haoqing Guo,Qiming Peng,Qiming Peng,Xian Kai Chen,Qinying Gu,Shengzhi Dong,Emrys W. Evans,Alexander J. Gillett,Xin Ai,Ming Zhang,Dan Credgington,Veaceslav Coropceanu,Richard H. Friend,Jean-Luc Brédas,Feng Li,Feng Li +15 more
TL;DR: Donor–acceptor neutral radicals based on an electron-poor perchlorotriphenylmethyl or tris(2,4,6-trichlorophenyl)methyl radical moiety combined with different electron-rich groups are designed, providing a simple molecular-design strategy for stable, highly luminescent radicals with non-Aufbau electronic structures.
Journal ArticleDOI
Triplet–Polaron-Interaction-Induced Upconversion from Triplet to Singlet: a Possible Way to Obtain Highly Efficient OLEDs
Ablikim Obolda,Qiming Peng,Chuanyou He,Tian Zhang,Jiajun Ren,Hongwei Ma,Zhigang Shuai,Feng Li +7 more
TL;DR: A triplet-polaroninteraction-induced upconversion from triplet to singlet through a one-electron transfer mechanism is proposed, and is proven by magnetocurrent measurement and quantum-chemistry computation.
References
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Journal ArticleDOI
Luminescent sensors and switches in the early 21st century
TL;DR: The ideas and experimental results within 350 references are marshalled to illustrate the design bases and application potential of molecular luminescent sensing and switching devices that have appeared since the turn of the century as mentioned in this paper.