Luminescence and thermometry sensing of Sr2InTaO6: Eu3+, Mn4+ phosphors in a wide temperature range.

Fluorescent temperature sensing materials are generally designed based on the phenomenon that the fluorescence intensity ratio (FIR) of luminescence at different wavelength positions changes linearly with temperature. Luminescence at different wavelength positions can come from two different luminescent centers. The key to the design of such materials is that the two luminescent centers have different degrees of change with temperature, that is, they have different thermal quenching behavior. Herein, we have investigated the luminescence properties and structure of Eu3+ and Mn4+ co-doped in Sr 2 InTaO 6. The emission of doped Eu3+ (rare earth) changes little with the increase of temperature. However, the emission of doped Mn4+ (transition metal) decreases sharply with increasing temperature. Materials in two different temperature ranges (80–300 K under room temperature, and 300–523 K above the room temperature) have shown a satisfactory temperature sensing performance. This work points out a direction for the design of temperature sensing materials based on the FIR of two luminescent centers, that is, mixing an ion with excellent luminescence thermal stability (such as rare earth ion Eu3+, Sm3+, Dy3+, etc.) as a reference, and an ion with relatively poor luminescence thermal stability (such as transition metal Mn4+, main group element ion Bi3+, etc.) as the temperature scale. • A series of Sr 2 InTaO 6 : x Eu3+, 0.005Mn4+ phosphors were synthesized by conventional high-temperature solid-phase reaction. • The FIR was used to design fluorescent temperature sensing materials with linear change of temperature. • As the temperature increases, the emission intensity of Eu3+ (5D 0.→7F 2) and Mn4+ (2E g →4A 2g) decreased to different degrees, that is, the sensitivity of Eu3+ and Mn4+ to temperature are different. • The temperature sensing properties of Sr 2 InTaO 6 : 0.06Eu3+, 0.005Mn4+ phosphor were studied at 80–300 K and 298–523 K. • The equation was used to fit FIR and temperature, and S a and S r were calculated. S a = 0.056 K−1 at 80 K, S r = 0.72 %K−1 at 240 K, S a = 0.068 K−1 at 298 K, S r = 1.38 %K−1 at 398 K. [ABSTRACT FROM AUTHOR]