Characterization of the phosphor (Sr,Ca)SiAlN3: Eu2+ for temperature sensing
Ellen Hertle, Jonas Bollmann, Simon Aßmann, Violetta Kalancha, Andres Osvet, Miroslaw Batentschuk, Stefan Will, Lars Zigan
Journal of Luminescence
Laser-induced phosphorescence based on luminescent particles is a suitable technique for remote temperature sensing. The luminescence characteristics of the phosphor (Sr,Ca)SiAlN3:Eu2+ (”SCASN”) were investigated regarding the suitability of the material for phosphor thermometry. The phosphor has a high quantum efficiency, a very broad excitation band, an emission peak centered at about 620 nm and a short lifetime of less than 1μs, which makes it promising for thermometry measurements. After excitation at 532 nm, the luminescence emission reveals a blue shift with increasing temperature, which can be used for temperature calibration based on the two-color intensity ratio method. The excitation and emission characteristics are favorable for measurements in environments containing fuels and oils, which tend to fluorescence after UV-excitation. The phosphor allows for measurements up to 800 K, with a quenching temperature of 530 K. Spectral characteristics are presented for both bulk powder and a surface coating. For the former, a significant shift in the position of the emission peak is observed, which is most probably due to distinct re-absorption. A change in excitation laser fluence slightly affected the luminescence emission spectrum of both bulk material and coating and thus requires consideration in temperature determination.
Fluorescence, Photoluminescence, Materials, Sensors