Pr3+ doped new TZYN glasses and glass-ceramics containing NaYF4 nanocrystals: Luminescence analysis for visible and NIR applications

In this work, I have been prepared a series of different concentration of Pr3+ doped TeO2-ZnO-YF3-NaF (TZYN) new oxyfluoro tellurite glasses by conventional melt-quenching technique. The oxyfluoro glass-ceramics were obtained by controlled heat treatment of 0.2 mol% Pr3+ doped glass at 390 °C, equal to the crystallization temperature (Tc1) obtained from DSC analysis, for different time intervals 5, 10 and 15h. The precipitation of α-NaYF4 phase was confirmed by comparison of measured X-ray diffraction patterns with α-NaYF4 JCPDS patterns. In glass ceramics, the intensity of the transitions, 3P0→3F2, in VIS, and 1D2→3F4 & 1D2→1G4 in NIR regions was enhanced by 24.03, 9.4 and 4.54 times, respectively. Moreover, with heat treatment time, an experimental lifetime of the 3P0 excited state of Pr3+ ion was also enhanced from 24 μs in glasses to 62 μs in glass-ceramics due to by the enhancement of crystallite size of precipitation of NaYF4 nanocrystals.