Controllable synthesis and tunable luminescence of glass ceramic containing Mn2+:ZnAl2O4 and Pr3+ :YF3 nano-crystals

Glass ceramic containing spinel ZnAl2O4:Mn2+ and orthorhombic YF3:Pr3+ nano-crystals has been successfully prepared by a melt-quenching technique. X-ray diffraction and transmission electron microscopy demonstrated that two nano-phases, i.e. ZnAl2O4 and YF3, were homogeneously distributed among the glass matrix. Importantly, the selective incorporation of Pr3+ ions into the Y3+ nine-fold coordinated sites of YF3 and the segregation of Mn2+ dopants in the Zn2+ tetrahedral sites of ZnAl2O4 were confirmed based on the excitation/emission spectra and the crystal field calculation. Under blue light excitation, both Pr3+ and Mn2+ in the glass ceramic can be simultaneously excited, and emit red and green luminescence, respectively, owing to the suppression of energy transfer between them. The luminescence color of the obtained glass ceramic can be easily tuned by adjusting the excitation wavelength. These results indicate the potential application of the glass ceramic as converting phosphor to generate white-light after coupling with the blue LED chip. (C) 2015 Elsevier Ltd. All rights reserved.