Optimization of the thermometric performance of single band ratiometric luminescent thermometer based on Tb3+ luminescence by the enhancement of thermal quenching of GSA-excited luminescence in TZPN glass

Highlights: • TZPN glasses doped with Tb³⁺ ions were applied to luminescence thermometry. • Excitation lines matching GSA and ESA allowed for SBR approach to be applied. • The observed rapid thermal quenching of GSA-excited luminescence was discussed. • Optimizing the GSA-excited emission allowed to achieve high sensitivities. -- Abstract: Responding to the latest trends in luminescence thermometry, a new material of TZPN glass doped with Tb³⁺ ions was investigated for its use in the single band ratiometric approach. In contrast to the most of the Tb³⁺ doped phosphors emission intensity of Tb³⁺ ions in TZPN glass upon excitation matched to transitions from the ground ⁷F₆ level show strong thermal quenching of luminescence intensity. On the other hand for an excitation line matched to the absorption from the thermally coupled excited ⁷F₅ level, the emission intensity increases for temperature elevation. The ratio of these two signals is known to be an excellent temperature dependent parameter enabling a highly sensitive temperature readout. Strong thermal quenching of Tb³⁺ emission was discussed in terms of the thermally induced electron transfer from f state to the conduction band of the glass. In this work, it has been shown that optimization of the thermal quenching process is as important as the previously proposed optimizations of the intensity variability upon stimulation matched to excited state absorption. High relative sensitivities reaching 1–2%/°C were achieved, mainly because of the strong thermal quenching of the luminescence exhibited by the TZPN: Tb³⁺ glasses with different concentrations of dopant ions.