Figure 1.

Expanding emission lifetimes of carbon dots by forming hydrogen bonds with PVA that restrain triplet emission species leading to room temperature phosphorescence [19,20]. Information protection applications of m-CDs@nSiO₂. (a) Photographs of m-CDs@nSiO₂-PVA and m-CDs-PVA films under daylight, and irradiation with 365 nm UV lamp on and off when the films are desiccated and wetted; (b) Intensities of afterglow alterations of m-CDs@nSiO₂-PVA and RTP changes of m-CDs-PVA films under dry and wet conditions for five cycles; (c) Schematic illustration of information protection (encryption and decryption) processes by using m-CDs@nSiO₂-PVA, m-CDs-PVA, and m-CDs-PEG inks. (Reproduced with permission from ref. [19]. Copyright 2017 American Chemical Society, Washington, DC, USA).