Two-Color Cholesteric Liquid Crystalline Gels for Reversible Writing and Erasing Information Encryption

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Optoelectronics

Background:

• Cholesteric liquid crystals (CLCs) exhibit bright structural color due to their helical superstructure.
• Fluorescence color provides intrinsic emission but combining it with structural color in a self-supporting system is challenging.
• Photoresponsive materials offer tunable properties upon light stimulus.

Purpose of the Study:

• To synthesize a photoresponsive gelator for creating self-supporting CLC physical gels.
• To achieve independent regulation of structural color, fluorescence, and mechanical properties.
• To explore applications in reversible information encryption and anticounterfeiting.

Main Methods:

• Synthesis of a cyanostilbene-based gelator (CSpy-C10) with aggregation-induced emission (AIE) properties.
• Formation of thermo-/photoresponsive CLC physical gels by incorporating CSpy-C10 into liquid crystals.
• Characterization of structural color, fluorescence, and mechanical properties, and investigation of reversible information encryption.

Main Results:

• The synthesized CSpy-C10 successfully gels liquid crystals, forming CLC physical gels with tunable thermo-/photoresponsive behaviors.
• Independent control over structural color, blue fluorescence, and mechanical properties was achieved by separating functional units.
• Reversible information encryption (writing and erasing) was demonstrated based on fluorescence changes.

Conclusions:

• A novel two-color material system combining structural and fluorescence colors has been developed.
• The material offers independent tunability and reversible information encryption capabilities.
• Potential applications include information encryption, fluorescent displays, and high-tech anticounterfeiting.