SrAl12O19:Eu,Cr As Luminescence Thermometers

Abstract

Luminescent nanothermometers offer several approaches to determine the absolute temperature. Mostly, temperature-stimulated changes in the intensity ratio of emission bands, emission kinetics, band/emission line width, or luminescence band/line peak position are explored. The list is longer and is still growing. In our project, the Cr3+, Eu2+-based aluminates materials were designed taking into account the possibility to work as non-contact luminescent thermometers using mentioned above approaches. In Figure 1 the luminescence spectra of SrAl12O19:Eu,Cr phosphor are shown in the temperature range of 15-500 K. The emission comes from both the directly excited ions, Eu2+ and Cr3+. Particularly strong changes with temperature can be seen in the Eu2+ emission around 350 - 470 nm and Cr3+ above 670 nm. Luminescent mechanisms of energy transfer between specific activators of the aluminates lattice will be presented, the consequence of which is obtaining by the material sophisticated thermometric properties in a wide range of measured temperature, from cryogenic to around 500 K. The research finances by the Polish National Science Centre under grant #UMO2018/31/B/ST4/00924 and partially by program “Excellence Initiative – Research University” (IDUB) for years 2020-2026 for University of Wrocław (grant # BPIDUB.4610.678.2021) Figure 1