Bubble-Assisted Dynamic Confinement Enables Programmable Solid-State Photoswitching and Heterogeneous Photoresponsive...

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Photochemistry

Background:

• Programmable photoisomerization of azobenzenes in the solid-state is a significant challenge for photoresponsive materials.
• Controlling molecular aggregation and motion is crucial for solid-state photoresponsive behavior.

Purpose of the Study:

• To introduce a dynamic soft-confinement strategy for manipulating molecular aggregation.
• To achieve high-performance solid-state photoisomerization of azobenzenes.
• To enable programmable photoresponsive materials for photomechanical applications.

Main Methods:

• Bubble-assisted assembly to control surface energy at the solid-liquid interface.
• Utilizing microfluidic channels with varying morphologies (necktie-like, strip-like, necklace-like) to influence aggregate structures.
• Multi-scale characterization and computational analyses to understand aggregation kinetics and molecular motion.

Main Results:

• Achieved distinct self-assembled aggregates (microcubes, corded scaffolds, microplates) with tailored molecular freedom.
• The strip-like channel design yielded a corded scaffold enabling near-quantitative bidirectional E⇆Z photoisomerization (96%-98%) in the solid-state.
• Demonstrated heterogeneous patterning for programmable photoresponsive arrays.

Conclusions:

• Dynamic soft-confinement via bubble-assisted assembly is a scalable strategy for controlling supramolecular self-assembly pathways.
• This approach enables the design of solid-state photoresponsive materials with performance rivaling solution-like systems.
• The developed platform facilitates the creation of programmable photoresponsive materials for diverse applications.