Eu2+ ions and CaF2-containing transparent glass-ceramics

Transparent glass-ceramics have been prepared by heat-treating 45SiO2–20Al2O3–10CaO–25CaF2 glasses doped with Eu2+ ions (in mol%). The precipitated crystalline phase in the glass-ceramics was CaF2. TEM observation showed the precipitated crystalline phase had a size of 11–18 nm and dispersed in the amorphous phase without clustering. Fluorescence measurements showed that Eu2+ ions entered into the CaF2 crystalline phase and gave a much stronger emission in the glass-ceramics than in the corresponding glass.