Multiple optical thermometry and dynamic anti-counterfeiting based on multicolor luminescence of SrY2O4:Bi3+,Er3+ phosphor

Multifunctional materials with optical temperature sensing and anti-counterfeiting properties have vast application prospects in our daily life, but the development of them still faces huge challenges. Herein, a novel SrY2O4:Bi3+,Er3+ phosphor with multicolor luminescence was synthesized triumphantly. Stimulated by different ultraviolet (UV) lights, the sample exhibits blue or green emissions, while emits yellow up-conversion luminescence under 980 nm laser irradiation. Interestingly, abnormal thermal quenching and thermal stimulation enhanced persistent luminescence are realized in SrY2O4:Bi3+,Er3+. Benefiting from the distinct responses of Bi3+ and Er3+ luminescence to temperature, thermochromism is verified when excited by UV or 980 nm light. Furthermore, the color shift from yellow-green to dark yellow is seen as the 980 nm laser power density reduces or the distance between laser source and the sample increases. Based on the luxuriant luminescence properties, multimode optical temperature sensing and dynamic anti-counterfeiting are constructed. All findings indicate that the multicolor emissive SrY2O4:Bi3+,Er3+ material offers a fresh outline for the exploitation of multiple optical thermometry and anti-counterfeiting.