Effect of thermal treatment on excited state spectroscopy of oxyfluoride borosilicate glass activated by Pr3+ ions

In order to obtain new kind of glass ceramics (with improved mechanical strength, thermal and chemical resistance), oxyfluoride borosilicate (SiO2–B2O3–Na2O–LaF3) glass, containing Pr3+ ions (0.82–0.41 wt% Pr2O3), has been melted and then exposed to thermal treatment at 555 °C and 620 °C. Changes in the absorption and emission spectra and in the fluorescence kinetics are observed and analyzed. In this work we report in detail on the results of measurements along with interpretation which indicate an existence of a nano-crystalline phase in the glass as a result of thermal treatment.