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Photoinduced Radical Emission in a Coassembly System
Yiran Li1,2, Glib V Baryshnikov3, Chenggang Xu1
1State Key Laboratory for Modification of Chemical Fiber and Polymer Materials, National Manufacturing Innovation Center of Advanced Dyeing and Finishing Technology, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, P. R. China.
Angewandte Chemie (International Ed. in English)
|September 4, 2021
Summary
Researchers developed a method for stable radical emission at room temperature by combining tricarbonyl-substituted benzenes with polyvinyl alcohol. This breakthrough enables solid-state free radical emission for potential applications like information encryption.
Area of Science:
- Materials Science
- Photochemistry
- Organic Chemistry
Background:
- Generating radical emission at ambient conditions is difficult due to the instability of radical species in air.
- Previous methods often require specialized conditions to maintain radical stability.
Purpose of the Study:
- To develop a stable method for free radical emission at ambient conditions.
- To explore the use of coassembled tricarbonyl-substituted benzenes and polyvinyl alcohol (PVA) for this purpose.
- To investigate the underlying mechanism and potential applications of the observed radical emission.
Main Methods:
- Coassembly of tricarbonyl-substituted benzene molecules with polyvinyl alcohol (PVA).
- Photoirradiation of the coassembled materials.
- Investigation of radical emission properties under varying temperatures and functional groups.
- Quantum-chemical calculations to elucidate the emission mechanism.
Main Results:
- Achieved strong solid-state free radical emission by protecting radicals within a PVA host matrix via hydrogen bonding.
- Demonstrated that temperature and molecular functional groups influence emission intensity.
- Quantum-chemical calculations suggest emission originates from anti-Kasha D2 → D0 vertical emission of anion radicals.
- Successfully applied photoinduced radical emission for information encryption.
Conclusions:
- Tricarbonyl-substituted benzenes coassembled with PVA provide a viable route for stable ambient radical emission.
- The developed system offers tunable emission properties and a novel mechanism for information encryption.
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