Silica-based oxyfluoride glass and glass-ceramic doped with Tm3+ and Yb3+ -VUV-VIS-NIR spectroscopy and optical thermometry

摘要

Optical, structural and morphological properties of Tm3+/Yb3+ co-doped NaYF4-based nano-glass-ceramic and a precursor glass have been investigated. The controlled heat-treatment of multicomponent oxyfluoride glass at 640 degrees C for 2 h was used to obtain crystalline precipitations. The differences in optical characteristics have been discussed analysing spectra recorded within wide VUV-VIS-NIR spectral range and considering relaxation dynamic of involved excited states. Optical spectra and luminescence decay curves were measured as a function of temperature in the range of 295-725 K. Based on up-converted emission spectra excited at 975 nm, temperature sensing properties of glass-ceramic were verified. The fluorescence intensity ratio between the up-converted emission bands located at around 795 nm (Tm3+:H-3(4)-H-3(6)) and 695 nm (Tm3+:3F(3,2)-H-3(6)) was studied. The maximum relative temperature sensitivity was determined to be 0.35% K-1 at 445 K. (C) 2019 Elsevier B.V. All rights reserved.