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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
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Generation of Long-Lived Photoinduced Charge Separation in a Supramolecular Toroidal Assembly
Sumesh B Krishnan1,2, Karical R Gopidas1,2
1Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695 019, India.
The Journal of Physical Chemistry. B
|September 8, 2020
Summary
Researchers created a self-assembled anthracene-methyl viologen system that forms toroidal nanostructures. This system successfully generates long-lived charge-separated states via photoinduced electron transfer, overcoming rapid back-transfer limitations.
Area of Science:
- Supramolecular Chemistry
- Photochemistry
- Materials Science
Background:
- Artificial photosynthesis and photocatalysis rely on generating long-lived charge-separated (CS) states.
- Ultrafast back electron transfer often limits the efficiency and quantum yield of CS states in photoinduced electron transfer (PET) reactions.
Purpose of the Study:
- To achieve long-lived CS states in PET reactions.
- To investigate hierarchically self-assembled donor-acceptor systems for enhanced photophysical properties.
Main Methods:
- Hierarchical self-assembly of anthracene-β-cyclodextrin (CD-AN-CD) and methyl viologen-adamantane (AD-MV2+-AD) inclusion complexes in water.
- Formation of toroidal nanostructures.
- Photophysical studies to investigate PET and CS state generation.
Main Results:
- Well-defined toroidal nanostructures were successfully formed through hierarchical self-assembly.
- Photoinduced electron transfer from anthracene to methyl viologen was confirmed by fluorescence quenching.
- A long-lived charge-separated state was generated upon irradiation of the aqueous toroidal solution.
Conclusions:
- Hierarchical self-assembly provides a viable strategy for creating nanostructures that facilitate long-lived charge separation.
- The developed anthracene-methyl viologen system demonstrates significant potential for applications in artificial photosynthesis and photocatalysis.
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