The Research On Preparation And Luminescence Properties Of Rare-earth Doped Transparent Oxyfluoride Glass-Ceramics

In this paper, a series of Nd3+ions, Ho3+ions single doped and Er3+-Ho3+ions co-doped transparent oxyfluoride tellurite glass and glass ceramics were successfully prepared by using a conventional melt-quenching method. Some properties such as crystallization behaviors, microstructural, and their fluorescence properties were analyzed. The results showed that:After crystallization treatment, distributed uniformly, the particle diameter around50nm, global primary SiO2nanocrystals phases and secondly β-NaCaAlF6nanocrystals phases were precipitated in the glass matrixs; the optical transmittance of transparent glasses and glass-ceramics in the visible-near-infrared wavelengths were70～80%and45～70%, respectively.Under808nm excited, Nd3+ion doped transparent glasses and glass-ceramics had1.35μm、1.06μm and900nm three emission bands corresponding to4F3/2�'4I134F3/2�'4I11/2and4F3/2�'4I13/2energy transitions of Nd3+ions, respectively. The fluorescence intensity of all the three emission bands firstly increased and then decreased with Nd3+ions concentration increasing due to concentration quenching effect and the upconversion process of Nd3+ions. Full width at half maximum (FWHM) of1.06μm fluorescence was between20to40nm; at the same time, fluorescence intensity of glass-ceramics was significantly higher than that of corresponding glasses, the fluorescence intensity increased with crystallization time increasing in the same temperature. Finally, energy transfer mechanism between the Nd3+ions was analyzed in detail.Under488nm excited, Ho3+ions doped transparent glasses and glass-ceramics had548nm、659nm and755nm three emission bands corresponding to5S2(5F4)�'5I8、5F5�'5I8and5S2(5F4)�'5I7energy transitions of Ho3+ions, respectively. The fluorescence intensity of all the three emission bands firstly increased and then decreased; 896nm near-infrared fluorescence was found in the fluorescence spectra of the glass-ceramics sample with crystallized time extension. In addition, fluorescence intensity of glass-ceramics was significantly higher than that of corresponding glasses, it was the further evidence that a part of Ho3+ions participated into the lattice of nanocrystalline after crystallization processing; at last, energy transfer mechanism between the Ho3+ions was studied in detail.The strong1.53μm fluorescence was found in the Er3+-Ho3+co-dpoed transparent glasses and glass-ceramics systems under the excitation of980nm.1.53u m fluorescence intensity decreased gradually with Ho3+ions concentration increasing, it was mainly due to energy transfer between Er3+ions and Ho3+ions、concentration quenching effect of Ho3+ions and up-conversion luminescence process. Furthermore, fluorescence intensity of glass-ceramics was significantly higher than that of corresponding glasses, it was the further evidence that a part of Er3+ions and Ho3+ions participated into the lattice of nanocrystalline after crystallization processing; ultimatly, energy transfer process between Er3+ions and Ho3+ions and the luminescence mechanism were studied in detail:under980nm excited,4S3/2(Er3+)+5I8s(Ho3+)�'4I15/2(Er3+)+5S2(5F4)(Ho3+),4F9/2(Er3+)+5I8(Ho3+)�'4I15/2(Er3+)+5F5(Ho3+),4I13/2(Er3+)+5I6(Ho3+)�'4I15/2(Er3+)+5F5(Ho3+)2H11/2(Er3+)+5I6(Ho3+)�'4F9/2(Er3+)+5F5(Ho3+), energy transfer made1.53μm fluorescence intensity decrease.