Doping SrAl2O4:Eu2+, Dy3+and Thermochromic Materials for the Generation of Anticounterfeiting Membrane

Anticounterfeiting is a significant technique in modern society. Traditional static photoluminescent anticounterfeiting technique generally emits unicolor, which is simple to be faked. In this study, a multilevel anticounterfeiting device based on SrAl2O4:Eu2+, Dy3+/Thermochromic microcapsules/Polyacrylonitrile (SAOED/TCM/PAN) was developed. The reversible thermochromic microcapsules phase change material and persistent luminescent material SrAl2O4:Eu2+, Dy(3+)phosphors were served as functional fillers. The properties of SAOED/TCM/PAN on the reflectance and fluorescence spectra, morphology, thermal stability and thermochromic performance were experimentally investigated using fluorescence Spectrometer, scanning electron microscope (SEM), thermogravimetric analyzer (TGA), X-ray Diffraction (XRD) patterns, and et al. The results made clear that thermochromic microcapsules and SrAl2O4:Eu2+, Dy(3+)phosphors distributed in matrix evenly. The SAOED/TCM/PAN membrane exhibited tricolor (purple, red, and white) with the change of temperature and could be easily irradiated by a wide range of ray from ultraviolet to visible light. By employing the long afterglow luminescence and reversible tricolor thermochromism, we accomplished a high level anticounterfeiting. The reversible thermochromic and persistent luminescent characteristics of SAOED/TCM/PAN are facilely detected by using a heat-producer and a cheap portable lamp, which is extremely hard to be faked. Accordingly, this reversible thermochromic and persistent luminescent material could make SAOED/TCM/PAN attractive for anticounterfeiting designs. (c) 2020 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.