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Towards Optical Information Recording: A Robust Visible-Light-Driven Molecular Photoswitch with the Ring-Closure
Pan Hong1, Jing Liu1, Kai-Xuan Qin1
1Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan, 430074, China.
Angewandte Chemie (International Ed. in English)
|December 21, 2023
Summary
This study introduces TPAP-DTE, a novel molecular photoswitch activated by visible light. It achieves high yields for reversible switching, enabling advanced optical information storage applications.
Area of Science:
- Materials Science
- Organic Chemistry
- Photochemistry
Background:
- Diarylethene molecular photoswitches are key for optical information materials due to bistability.
- Conventional diarylethenes require UV light for switching, limiting practical applications.
- Visible-light-driven diarylethenes are desired, but achieving high yields is challenging.
Purpose of the Study:
- To synthesize a novel all-visible-light-driven photoswitch.
- To achieve high ring-closure reaction yields using visible light.
- To demonstrate practical applications in optical information recording.
Main Methods:
- Synthesized TPAP-DTE by endcapping dithienylethene (DTE) with triphenylamine phenyl (TPAP) groups.
- Utilized 405 nm visible light for ring-closure and long-wavelength visible light for ring-opening.
- Confirmed reaction yields using nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC).
Main Results:
- Achieved over 96.3% ring-closure yield for TPAP-DTE upon 405 nm irradiation.
- Demonstrated 100% ring-opening yield with long-wavelength visible light.
- Exhibited robust fatigue resistance (100+ cycles) and anti-aging properties (1000+ hours at 85°C/85% humidity).
Conclusions:
- TPAP-DTE functions as a highly efficient, visible-light-driven molecular photoswitch.
- The developed photoswitch shows "quasi"-quantitative bidirectional conversion.
- Demonstrated potential for rewritable QR codes, data storage, and anti-counterfeiting applications using visible light.
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