Synthesis and luminescent properties of GdSrAl3O7:Tb3+ phosphor under VUV/UV excitation

Superfine powder of Tb3+ ion-doped aluminates phosphors, GdSrAl3O7:Tb3+ was synthesized with a precursor prepared by an EDTA-sol–gel method at 900 °C. Field-emission scanning electron-microscopy (FE-SEM) observation indicated a narrow size-distribution of about 150–300 nm for the particles with elliptical shape. Upon excitation with vacuum ultraviolet (VUV) and near UV light excitation, the phosphors show a strong emission line at around 542 nm corresponding to the 5D4 → 7F5 transition of Tb3+, and the highest PL intensity at 542 nm was found at a content of about 12 mol% Tb3+. As the Tb3+ concentration increases, Tb ions strongly cross-relaxation interact resulting in a decrease of the lifetime. The results reveal that GdSrAl3O7:Tb3+ would be a promising green phosphor for PDP application.