Preparation And Spectral Properties Of Pr³⁺-doped Glass Ceramics Containing LiYF₄ Nanocrystals

Pr3+ doped transparent oxyfluoride glass ceramics containing LiYF4 nanocrystals were synthesized by melting-quenching and subsequent thermal treatment method in this work.The crystallization phase and microstructure of the glass ceramics were investigated by X-ray diffraction and transmission electron microscope,respectively.The absorption spectra,emission spectra and fluorescence decay curves of the glass and glass ceramic were measured at room temperature.Firstly,in the melting temperature of 1450℃,the research of glass formation region by adjusting the SiO2/Al2O3 ratio,and study of different types,different content of alkali/alkali-earth metal oxides and LiF/YF3 ratio influence on the glass crystallization.The glass composition of precipitation LiYF4 nanocrystals is 40SiO2-25Al203-5Na2O-20LiF-10YF3.Then,the X-ray diffraction and transmission electron microscope experiments show the existence of LiYF4 nanocrystals with average sizes of 20～35nm in the glass ceramics.Finally,the analyses of absorption and emission spectra demonstrate that a part of Pr3+ ions have been incorporated into the LiYF4 nanocrystals.From the fluorescence decay curves,the fluorescence lifetime of 3P0 level of Pr3+ ion in the glass ceramics longer than that of the glass is calculated.