Preparation and anti-counterfeiting application of phosphorescent carbon dots based on pickled skin

Phosphorescent carbon dots (P-CDs) were prepared by pyrolysis method using pickled skin as carbon source and boric acid as boron source. The effects of pickled skin content, reaction pH, reaction temperature and reaction time on the afterglow time of P-CDs were investigated. The P-CDs obtained were characterized by organic element analyzer, SEM, EDS, TEM, FTIR and XRD, and evaluated for the anti-counterfeiting application. The results showed that the P-CDs, prepared with pickled skin content (based on 3 g boric acid, the same below) of 4.10%, reaction pH of 7, reaction temperature of 225 ℃, and reaction time of 7.5 h, displayed the longest afterglow time of 12 s. The material exhibited an optimum emission wavelength of 520 nm corresponding to a bright green afterglow, and an average particle size of 4.42 nm with a typical graphite structure. Boron atoms were successfully incorporated into the P-CDs to form C—B, B—O conjugate chain structure, which stabilized the triple excited state and prolonged the afterglow time. © 2024 Fine Chemicals. All rights reserved.