Enhanced luminescent properties of Ca3−xTbxZrSi2O9+x/2 phosphors by Al3+ doping into the Zr4+ site in the host lattice

Green-emitting Ca3−xTbxZr1−yAlySi2O9+(x-y)/2 (0.05≤x≤0.20, 0≤y≤0.07) phosphors were synthesized in a single phase form by the conventional solid-state reaction method and their photoluminescent properties were investigated. These phosphors exhibited typical emission peaks assigned to the transition from 5D4 to 7FJ (J=3, 4, 5, and 6) of Tb3+, and the luminescence emission intensity was effectively enhanced by the Al3+ doping into the Zr4+ sites of the host Ca3ZrSi2O9 lattice. The highest emission intensity was obtained for Ca2.91Tb0.09Zr0.95Al0.05Si2O9.02, where the relative emission intensity was as high as 33% compared with that of a commercial green-emitting (La0.52Ce0.31Tb0.17)PO4 phosphor.