Visual ratiometric optical thermometer with high sensitivity and excellent signal discriminability based on LiScSiO:Ce, Tb thermochromic phosphor.

Developing optical thermometer phosphors with high sensitivity, high signal discriminability and strong fluorescence intensity is ongoing. A dual-emitting thermochromic phosphor, LiScSiO:Ce, Tb, was successfully synthesized via solid-state reaction method. The crystal structure, electronic structure, luminescent performance and thermal luminescence behaviors as well as the luminescence mechanism of LiScSiO:Ce, Tb were systematically investigated. Due to the energy transfer and different thermoluminescence behaviors between Ce and Tb, high relative sensitivity (2.2 % K@473 K), excellent signal discriminability (5747 cm), outstanding temperature resolution (0.067 K) and good repeatability, as well as efficient emission at high temperatures were achieved based on the fluorescence intensity ratio of Ce and Tb, indicating its potential in ratiometric optical thermometer. Moreover, the excellent visualizing thermochromic enable LiScSiO:Ce, Tb to be used as safety sign in variable temperature environment to monitor temperature distribution.