Effect of Mg2+/Sr2+ addition on luminescence properties of Dy3+ doped glass ceramics containing Ca2Ti2O6

Abstract

Dy2O3-doped transparent glass-ceramics containing Ca2Ti2O6 crystal phase were synthesized by melting crystallization method. The optimum heat treatment condition was determined to be 710 °C/1.5 h by differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmittance curves. The optimal doped concentration of Dy2O3 is 0.4 mol%. The effects of doping with different concentrations of Mg2+ and Sr2+ on the fluorescence intensity of glass-ceramics were discussed. In comparison to Sr2+, the addition of Mg2+ effectively increased the luminescence intensity of 0.4 mol% Dy2O3-doped glass-ceramics. Since Mg2+ has a smaller ionic radius, it has a larger Coulomb potential and is more attractive to O2−, which makes the three-dimensional skeleton of BO6 tilt, and the symmetry of the structure deteriorates, resulting in enhanced luminescence. Comparison of 0.4 mol%Dy2O3-doped glass-ceramic and 8 mol%MgF2-0.4 mol%Dy2O3 co-doped glass-ceramic, the fluorescence intensity increased by 56.8% at 484 nm and 83.5% at 577 nm, the optical band gap value was reduced from 2.7824 eV to 2.4341 eV. The findings suggest that Dy3+-doped glass-ceramics containing Ca2Ti2O6 crystal phase will be used in white light-emitting diodes (W-LEDs).