The usability of the Judd-Ofelt theory for luminescent thermometry using Eu3+-doped phosphate glass.

The Judd-Ofelt theory, which is the most thorough and insightful method to determine theoretically the luminescent properties of the trivalent rare earth dopants, is here tested on Eu3+-doped glasses in the P 2 O 5 – SrO – CaO – Na 2 O system to assess their usefulness as luminescent thermometers. It is demonstrated that the thermometric sensitivity (change of the emission lines ratio in response to change in temperature) can be estimated using the Judd-Ofelt theory and aligns well with the experimentally obtained values. It is shown here that the addition of B 2 O 3 or SiO 2 in a phosphate network increases the absolute sensitivity due to an increase in the phosphate network connectivity while having no significant impact on the site of Eu3+ ions. The applicability of the Judd-Ofelt theory for predicting the thermometric parameters of a glass luminescent material, without the time-consuming measurement of the glasses spectroscopic properties as a function of temperature, is clearly demonstrated and allows for further development of novel efficient luminescent thermal sensors with high sensitivity. [Display omitted] • The luminescent thermometer performance of Eu3+-doped glasses is predicted by Judd-Ofelt theory. • The structure connectivity of the studied glass is increased by the addition of 5% of SiO 2 or B 2 O 3 (for P 2 O 5). • The increase in structure connectivity enhances the absolute sensitivity of Eu3+ luminescent thermometer. • Refractive index is the most determining factor in the enhancement of the absolute sensitivity. [ABSTRACT FROM AUTHOR]