Phosohor-Based Temperature-Sensitive Paints for Thermometry: Material Development & Characterization

Kurzfassung

Temperature-sensitive paints (TSPs) enable non-contact, spatially resolved temperature measurements and have therefore become highly attractive for applications in which conventional temperature sensors provide only limited information or are difficult to implement on complex surfaces [1–3]. Classical TSPs are mostly organic coating systems that rely on thermal quenching processes of luminescent molecules or complexes. Although such systems are well established, their applicability is inherently limited at elevated temperatures, since both the organic luminophores and the organic binder tend to lose stability or degrade under harsh thermal conditions [1]. If temperature measurements are to be extended into higher-temperature regimes, inorganic phosphors and inorganic binders therefore become necessary. This challenge is directly connected to the broader field of luminescence thermometry, which addresses temperature determination by means of temperature-dependent luminescent properties such as emission intensity, spectral characteristics, or decay time [4–9]. In recent years, this field has attracted considerable attention because inorganic luminescent materials often combine good chemical stability, high thermal resistance, and strong optical response. At the same time, the transfer of such concepts into coating-based systems remains highly relevant for practical applications, especially when phosphor-based TSPs are intended for demanding thermal environments.