A color-tunable persistent luminescence material LiTaO3:Pr3+ for dynamic anti-counterfeiting

In this work, an original color-tunable persistent luminescence (PersL) phosphor based on Pr3+ doped LiTaO3 (LTO) was realized. The PersL emission can be modulated from pale yellow to deep orange-red merely by changing the concentration of Pr3+, which attributed to the concentration quenching resulted from the cross-relaxation (CR) effect. Thermoluminescence (TL) analysis shows that the continuous shallow traps (0.668–0.8 eV) are suitable for PersL. Moreover, it also exhibits excellent photostimulated luminescence (PSL) performance owing to the presence of stable deep traps of 0.916 eV. A possible PersL mechanism of LTO:Pr3+ is put forward to explain this phenomenon. Finally, inspired by this multicolor PersL feature, a quick response code (QR-code) and an arrow pattern are developed, revealing that LTO:Pr3+ is an ideal material for dynamic anti-counterfeiting. Our work is designed to promote the practical applications of PersL materials in information security areas.