Dual-Wavelength Zn0.2Ga1.1Si0.9O3.65:Cr Persistent Luminescence Nanoparticles for Dynamic Multimode Anticounterfeiting

Persistent luminescence nanoparticles (PLNPs) can provide long afterglow after excitation and possess advantages for advanced optical anticounterfeiting. Nevertheless, PLNPs with dual-wavelength persistence luminescence for dynamic and multimode anticounterfeiting are just at the initial stages. Herein, we synthesized dual-wavelength (503 and 696 nm) afterglow PLNPs Zn0.2Ga1.1Si0.9O3.65:Cr (ZGSiO:Cr) using a hydrothermal method followed by calcination. The luminescence color and the afterglow time of PLNPs are tunable through the content of Si4+. The colors of the emission, including red, white, cyan, and purple, could be observed under single ultraviolet (UV)-light irradiation; the PLNPs show the visible afterglow emission, after UV-light irradiation. The as-prepared ZGSiO:Cr exhibits high-level, dynamic, and multimodal anticounterfeiting with facile and quick operation and low cost and provides a more convenient and effective method for multimode anticounterfeiting, encryption, and currency information tracking.