Thermometric Judd-Ofelt model for Dy³⁺ ion tested in CaYAlO<inf>4</inf> host and evaluation of its sensing performances for luminescence thermometry

Abstract

Luminescence thermometry uses temperature-dependent emission of light for remote sensing. Dy3+ is established as a perspective ion for high-temperature probes, but given that there is an infinite number of potential hosts it is impossible to find conventionally the one with the best performance. Judd-Ofelt thermometric model can predict sensitivities but it was not yet experimentally validated on Dy3+ ion. Pure phase CaYAlO4:Dy3+ powder was synthesized via the modified Pechini method. Photoluminescence spectra were taken from 300 to 600 K. Luminescence intensity ratio was estimated using 4I15/2 and 4F9/2 levels. Experimentally obtained thermometric parameters and sensitivities showed an excellent matching with those obtained from the Judd-Ofelt, indicating the potential application of the Judd-Ofelt model for fast assessment of Dy3+-doped luminescent sensor thermometric perspective. The maximum absolute and relative sensitivities are ∼0.001 K−1 at 600 K and ∼1.4% K−1 at 300 K, respectively. The optimum temperature range for the CaYAlO4:Dy3+ probe is from 370 to 616 K.