Switching Diarylethenes Reliably in Both Directions with Visible Light
Sebastian Fredrich1, Robert Göstl1, Martin Herder1
1Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489, Berlin, Germany.
Angewandte Chemie (International Ed. in English)
|December 15, 2015
Summary
This study developed a novel conjugated photoswitch with enhanced fatigue resistance. The diarylethene photoswitch utilizes triplet energy transfer for efficient, reversible switching with visible light.
Area of Science:
- Organic Chemistry
- Photochemistry
- Materials Science
Background:
- Diarylethenes are photochromic compounds with potential applications in molecular switches.
- Improving fatigue resistance and enabling visible-light switching are key challenges in diarylethene research.
Purpose of the Study:
- To design and synthesize diarylethene photoswitches with improved photochromic performance.
- To investigate the effect of conjugated triplet sensitizers on diarylethene switching properties.
- To achieve efficient and robust visible-light switching of diarylethenes.
Main Methods:
- Covalent connection of diarylethene cores with triplet sensitizer moieties (biacetyl).
- Synthesis of conjugated and nonconjugated diarylethene derivatives.
- Investigation of photochromic performance, including fatigue resistance and switching efficiency under visible-light irradiation.
Main Results:
- The conjugated photoswitch exhibited superior fatigue resistance compared to the parent diarylethene and nonconjugated analogs.
- Effective triplet energy transfer from biacetyl to the diarylethene core was observed.
- Efficient and robust bidirectional switching with visible light was achieved through extended π-conjugation and triplet manifold pathways.
Conclusions:
- Conjugated diarylethene photoswitches with triplet sensitizers offer enhanced fatigue resistance and visible-light switchability.
- Triplet energy transfer is a viable strategy for improving diarylethene photochromic performance.
- The developed photoswitches are promising for applications requiring efficient and durable molecular switching.
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