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Photo-mechanical effects in azobenzene-containing soft materials
Christopher J Barrett1, Jun-Ichi Mamiya2, Kevin G Yager3
1Department of Chemistry, McGill University, Montreal, Canada. christopher.barrett@mcgill.ca.
Soft Matter
|September 9, 2020
Summary
Azobenzene molecules reversibly change shape when exposed to light, inducing mechanical deformation in host materials. This review explores azobenzene
Area of Science:
- Materials Science
- Photochemistry
- Nanotechnology
Background:
- Reversible molecular shape change, exemplified by the natural rhodopsin-retinal system, is a key phenomenon.
- Azobenzene serves as a highly effective artificial photo-switch, mimicking natural systems with superior reversibility, speed, and ease of integration.
Purpose of the Study:
- To review the study and applications of azobenzene-based systems for light-induced reversible shape changes.
- To define and focus on the photo-mechanical effect, specifically light-induced macroscopic deformation.
Main Methods:
- Review of scientific literature on azobenzene photo-mechanics.
- Analysis of systems demonstrating reversible shape change via azobenzene incorporation.
- Distinguishing photo-mechanical effects from thermal expansion and non-mechanical photo-switching.
Main Results:
- Azobenzene enables significant macroscopic mechanical deformation in host materials through light adsorption.
- The photo-mechanical effect is distinct from thermal effects and non-mechanical photo-switching.
- Azobenzene systems offer a versatile platform for light-controlled mechanical actuation.
Conclusions:
- Azobenzene is a powerful tool for creating photo-mechanical materials.
- Understanding and harnessing azobenzene's photo-mechanical properties opens avenues for novel applications.
- This review consolidates knowledge on azobenzene-driven photo-mechanics, excluding optical and electro-optical effects.
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