High-temperature dynamic luminescence of MgGa2O4: Tb3+, Er3+ phosphors for advanced anti-counterfeiting and information encryption

Abstract

Long persistent luminescence (LPL) anti-counterfeiting technology is widely used in optical information storage, information security, and anti-counterfeiting fields due to the advantages of non-interference with background light and high imaging resolution. However, the performance of most LPL materials is greatly compromised in harsh environments such as high temperature, which seriously affects the effectiveness of anti-counterfeiting measures due to the accelerated decay rate of LPL luminescence. In this work, we synthesized a series of MgGa2O4: Tb3+ (MGO: Tb3+), which possess stable crystal structure with obvious LPL properties above room temperature, and the optimum temperature is determined to be 423 K. Moreover, the additional introduction of Er3+ ions enhances the security of anti-counterfeiting, and the combination of photo-stimulated luminescence (PSL) and upconversion (UC) phenomena enables color tuning from red to orange to green by extending the 980 nm laser irradiation time. Finally, the anti-counterfeiting strategy utilizing MGO: Tb3+ and MGO: Tb3+, Er3+ possesses an extremely high level of security, making it an attractive performance for designing advanced anti-counterfeiting technology.