Cyclodextrin-Confined Supramolecular Lanthanide Photoswitch
Hua-Jiang Yu1, Haoran Wang1, Fang-Fang Shen1
1College of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 19, 2022
Summary
This study introduces a novel azobenzene-based nanosystem that achieves switchable lanthanide luminescence. By utilizing host-guest complexation, the system overcomes azobenzene
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Photochemistry
Background:
- Azobenzene photoisomerization controls morphology and biological processes.
- Azobenzene's light-quenching ability hinders photoluminescent nanoconstruct design.
Purpose of the Study:
- To develop an azobenzene-derived nanosystem with switchable photoluminescence.
- To explore its function as a supramolecular lanthanide photoswitch.
Main Methods:
- Utilizing metal chelation between lanthanide ions (Eu3+, Tb3+) and 2,6-pyridinedicarboxylic acid as the light-emitting center.
- Employing α-cyclodextrin to confine trans-azobenzene, enabling luminescence recovery.
- Reversibly switching luminescence off by expelling cis-azobenzene from α-cyclodextrin via light irradiation.
Main Results:
- Azobenzene's disordered motion initially suppresses lanthanide fluorescence.
- Hydrophobic cavity of α-cyclodextrin immobilizes trans-azobenzene, restoring lanthanide luminescence.
- Luminescence is reversibly switched off upon cis-azobenzene expulsion.
Conclusions:
- Host-guest complexation and metal-ligand coordination enable photoswitchable luminescence in azobenzenes.
- This approach holds promise for creating advanced light-responsive smart materials.
Keywords:
azobenzeneconformational confinementcyclodextrinlanthanide complexesswitchable luminescenceMore Related Videos
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