Upconversion luminescence and temperature sensing properties of CaF₂-crystal-contained silicate glass-ceramics doped with Er³⁺/Yb³⁺

Rare earth upconversion luminescent materials have a wide range of applications in the fields of anti-counterfeiting, imaging, temperature sensing, spectral conversion and so on. CaF2-crystal-contained glass-ceramics possess low phonon energy and good stability. Therefore, as a matrix material doped with rare earth, CaF2-crystal-contained glass-ceramics should have better upconversion luminescence properties. In this paper, the upconversion luminescence properties of Yb3+/Er3+-co-doped CaF2-crystal-contained silicate glass-ceramics were studied. Er3+/Yb3+-co-doped CaF2-crystal-contained silicate glass-ceramics were synthesized by melt-cooling method. XRD proved that CaF2 crystals were successfully precipitated in the glass. Comparing the upconversion luminescence intensity of different samples, the optimum heat treatment temperature was determined to be 660(degrees)C. The upconversion process was analyzed by analyzing the relationship between fluorescence intensity and excitation power. Finally, the relationship between the fluorescence intensity ratio of the sample at 521nm and 538nm with the temperature change was discussed, the absolute sensitivity and relative sensitivity of the sample to temperature were determined. The results show that the sample is expected to be used as a no-contact thermometer.