Mohammad Rezvani - Materials Science & Engineering, Tabriz University
Laleh Farahinia - Materials Science & Engineering, Tabriz University

 Oxyfluoride glass ceramics containing CaF۲nano-crystals doped with Y۳+ ions were prepared by one-step crystallization of SiO۲- Al۲O۳- CaO- CaF۲ glasses at different temperatures. X- ray diffraction (XRD) results have revealed that CaF۲ was the only precipitated crystalline phase in glass ceramic samples. According to the XRD results, a glass ceramic was selected as the best sample in order to compare its optical properties with basic glass. Photoluminescence (PL) and UV- Vis spectra have been employed to study optical properties of glass and glass ceramic samples. A broad band emission in the visible region was observed, which was stronger in the glassy sample. Scanning electron microscopy (SEM) observation and EDX (Energy-dispersive X-ray spectroscopy) results proved the entrance of Y۳+ ions into only some of the crystals embedded in the glassy matrix, which was the rational reason of photoluminescence intensity decrease in glass ceramic.

oxyfluoride glass ceramic, CaF۲nanocrystals, yttrium emission, luminescence