Yellow Fluorescent Hydrogel with Carbon Quantum Dots: An Innovative Guardian in the Field of Information Security

In the digital information era, the demand for advanced cryptographic protocols and anticounterfeiting technologies is increasingly intensifying. Leveraging their intrinsic stimuli-responsible characteristics, hydrogels have ascended as premier candidates for the development of anticounterfeiting materials. In this study, we have rapidly synthesized yellow fluorescent carbon quantum dots (Y-CQDs) via microwave irradiation and subsequently encapsulated them within a hydrogel to fabricate a nanocomposite hydrogel with yellow fluorescence. The hydrogel exhibits bright yellow fluorescence when excited by 365 nm UV light. By leveraging the property of Fe³⁺ to quench the fluorescence of Y-CQDs, as well as the coordination action between ethylenediamine tetraacetic acid disodium salt (EDTA-2Na) and Fe³⁺, it achieves the storage and erasure of information. This provides a new method for the encoding, storage, and reversible erasure of information.