Development and Application of Rare Earth-Doped Fluorescent Thermometry Materials

• • Er3+/Yb+ co-doped CeO2 upconversion thermometry achieves measurable luminescence up to 1570–1575 K, enabling non-contact temperature sensing in space applications where conventional thermocouples suffer from electromagnetic interference and require periodic recalibration. • • NaLuF4:Yb3+-Er3+-Ho3+ upconverting nanoparticles demonstrate multi-range fluorescence intensity ratio (FIR) thermometry in both visible and NIR regions, with the NIR range (1000–1700 nm) providing deeper tissue penetration for biomedical applications compared to visible-range thermometry. • • Silica core–shell structures on Er,Yb:GdVO4 upconversion nanoparticles enhance temperature sensing properties by mitigating surface quenching effects, with the core–shell architecture improving photostability and maintaining luminescence efficiency under physiological conditions. • • Thermographic phosphors enable turbine blade temperature measurements in operating aero engines, with the technique providing non-destructive, real-time thermal mapping that overcomes the limitations of contact-based thermocouples which are susceptible to environmental electromagnetic interference and material aging.