Dynamic metal-ligand coordination enables a hydrogel with rewritable dual-mode pattern display

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Optoelectronics

Background:

• Existing information display systems lack re-encoding capabilities.
• Dual-mode information display is crucial for enhancing information capacity and security.

Purpose of the Study:

• To develop a novel hydrogel-based optical platform for rewritable dual-mode information display.
• To utilize dynamic metal-ligand coordination for erasable optical information storage.

Main Methods:

• Fabrication of a hydrogel system with a poly(dodecylglyceryl itaconate) (pDGI) lamellar structure and poly(acrylamide)/poly(acrylic acid) (PAAm/PAAc) double networks containing fluorescent carbon dots (CDs).
• Exploitation of metal-ion coordination (Al3+) with carboxylic acid groups to induce changes in layer spacing and carbon dot aggregation.
• Utilizing ethylenediaminetetraacetic acid (EDTA) as a metal chelating agent to reverse the coordination and restore original optical properties.

Main Results:

• The coordination of Al3+ ions induced a blue shift in structural color and a red shift in fluorescent color by altering the hydrogel's layer spacing and carbon dot aggregation.
• The addition of EDTA successfully stripped Al3+ ions, reversibly restoring both the structural and fluorescent colors.
• Demonstrated an erasable dual-mode information display capability within the hydrogel platform.

Conclusions:

• The developed hydrogel system offers a viable platform for rewritable dual-mode information display.
• This work presents a new approach for developing advanced materials for erasable information protection and security.