Stabilizing Carbon Dot Phosphorescence in Aqueous Solutions by Hydrogen-Bonded Networks for Dual-Wavelength-Driven Information Encryption

Room-temperature phosphorescence (RTP) holds tremendous potential in various fields such as optoelectronic devices, bioimaging, and information security applications. However, achieving efficient RTP in aqueous environments has been a challenge due to nonradiative deactivation caused by dissolved oxygen and solvent-induced relaxation. In this study, we propose a design strategy to enhance the phosphorescence emission of carbon dots (CDs) in aqueous solutions by constructing hydrogen-bonded networks between CDs and ammeline (AM). The formation of robust hydrogen-bonded networks, combined with the synergistic effect of bound water, significantly enhances the phosphorescence emission by stabilizing the triplet excited states of CDs. Furthermore, the prepared AM-CD suspension exhibits an exceptionally long phosphorescence lifetime of up to 697.58 ms, showcasing its potential applications in two-photon information encryption and decryption.