The Institute

Title: Luminescent Platform for Thermal Sensing and Imaging Based on Structural Phase-Transition

Authors: Anam Javaid, Maja Szymczak, Malgorzata Kubicka, Vasyl Kinzhybalo, Marek Drozd, Damian Szymanski, Łukasz Marciniak

Journal: Advanced Science

DOI: 10.1002/advs.202508920   

The exceptional sensitivity of Eu³⁺ luminescence to structural variations in host lattices has been extensively studied over the years. Nevertheless, leveraging this property in materials undergoing thermally induced structural phase transitions for luminescence thermometry is a relatively recent development. Due to the inherently narrow operational temperature range of such thermometers, identifying and exploring new host materials is essential.

Addressing this challenge, the research group led by Prof. Marciniak investigates the temperature-dependent spectroscopic behavior of Na₃Sc₂(PO₄)₃:Eu³⁺ with varying dopant concentrations. Their findings reveal that Na₃Sc₂(PO₄)₃:Eu³⁺ undergoes a structural transformation from a low-temperature monoclinic phase to a high-temperature trigonal phase, inducing pronounced modifications in both the emission spectral profile of Eu³⁺ ions and the depopulation dynamics of the ⁵D₀ excited state.

As a result, this material proves suitable for both ratiometric and lifetime-based luminescent thermometry, achieving maximum relative sensitivities of 3.4% K^-1 and 1.0% K^-1, respectively. Furthermore, the study demonstrates that the thermal operating range can be effectively tuned through Eu³⁺ concentration adjustment to enhance thermometric performance.

Crucially, this work presents the first demonstration of ratiometric thermal imaging using a Eu³⁺-only doped phosphor captured with an unfiltered digital camera, highlighting Na₃Sc₂(PO₄)₃:Eu³⁺ as a highly promising candidate for advanced luminescence-based temperature sensing technologies.

This work was funded by the NCN Opus project UMO- 2022/45/B/ST5/01629