Excellent luminescent thermal stability of Dy/Sm co-activated multifunctional titanate single-phase phosphors.

Nowadays, the development of phosphors with excellent luminescent thermal stability for various applications has become a research hotspot. Therefore, the Dy/Sm co-activated multifunctional NaYTiO phosphors with excellent comprehensive performance in the field of non-contact optical measurement and white LED solid-state lighting were reported in this paper, and their crystal structure, elemental composition, optical bandgap and photoluminescence properties were systematically studied. Remarkably, the reason why NaYTiO:Dy,Sm phosphors achieved color-controlled emission from yellow to orange-red and even to white at the excitation wavelength of 363 nm was not based on the energy transfer process from Dy to Sm but on co-excitation. When the temperature reached 475 K, the luminescence intensity of the phosphor still maintained 96.75% of the initial intensity, demonstrating excellent thermal quenching property. Furthermore, the temperature sensing performance was evaluated by FIR technique according to the differential decreasing trend of Dy and Sm emission intensity with increasing temperature. Finally, we also certified the applicability of NaYTiO:Dy,Sm phosphors in white LEDs for indoor health lighting. These results indicate that NaYTiO:Dy,Sm multifunctional phosphors are promising dual functional luminescent platforms that can be used for non-contact optical thermometers and white LED device applications.