A stress-charged non-Newtonian-fluid persistent luminescent material

Abstract

Abstract It presents a BaSi2O2N2:Eu2+/PVA persistent luminescence (PersL) gel material that traps can be charged by stress instead of irradiation. It can emit green PersL without preirradiation at room temperature, and even after initial PersL disappears, stored PersL traces can be stimulated again at high temperature. The gel material is demonstrated to be a typical non-Newtonian fluid showing shear thinning characteristics and variable mechanical behaviors. It is viscous at low frequencies, but exhibits elastic behaviors at high frequencies. Typically, the gel material can be made into fixed shapes or pulled into strips. Also, it can be hard enough to bore holes on apples, elastic enough to bounce and even melt. Furthermore, the gel material shows good stability, self-healing, water resistance and biocompatibility. Some typical intelligent light-emitting devices based on the BaSi2O2N2:Eu2+/PVA gel material are designed to show potential applications in safety signage, emergency lighting, anticounterfeiting and tooth occlusion analysis.