NaYTi2O6: Pr3+ phosphors enabling dual-mode optical thermometry and persistent luminescence for anti-counterfeiting

Pr 3+ -doped NaYTi 2 O 6 phosphors show strong red emission and persistent luminescence. • Dual-mode thermometry gives maximum relative sensitivities of 2.77%K −1 and 4.02%K −1 . • Red persistent-luminescence decay enables time-resolved dynamic anti-counterfeiting. Developing multifunctional phosphors suitable for both anti-counterfeiting and optical thermometry applications remains challenge. Herein, a series of NaYTi 2 O 6 : Pr 3+ phosphors were synthesized, and their luminescence properties, temperature sensitivity and potential applications were systematically investigated. Under ultraviolet excitation, the phosphors exhibited prominent red emission at 614 nm ( 1 D 2  →  3 H 4 ) along with weaker emissions centered at 690 nm ( 3 P 0  →  3 F 3 ). Notably, red persistent luminescence (PersL) can also be observed from the NaYTi 2 O 6 : Pr 3+ phosphor. Based on thermoluminescence analysis, a feasible persistent afterglow mechanism of the phosphors was presented and discussed. Furthermore, luminescent patterns are fabricated by utilizing these phosphors as inks for anti-counterfeiting applications. In addition, the thermometric mode based on the normalized integrated intensity over 580–650 nm delivers a maximum relative sensitivity ( S r ) of 2.77%K −1 . Further FIR thermometry constructed from the Pr 3+ 1 D 2  →  3 H 4 and 3 P 0  →  3 F 3 transitions achieves a higher maximum S r of 4.02%K −1 . These results indicate that NaYTi 2 O 6 : Pr 3+ phosphor with persistent luminescence has potential applications in anti-counterfeiting and optical thermometry. Download: Download high-res image (90KB) Download: Download full-size image