Eu2+ and Dy3+ co-doped Sr3Al2O6 red long-afterglow phosphors with new flower-like morphology

Abstract

Abstract The detailed preparation process of Eu 2+ and Dy 3+ ion co-doped Sr 3 Al 2 O 6 flower-like phosphor powders with red long afterglow by a sol–gel method in the reducing atmosphere is reported. X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectrophotometer are employed to characterize the phosphor powders. The results reveal that Sr 3 Al 2 O 6 : x Eu 2+ , y Dy 3+ ( x =4, 8, 10, 20 mol%, y =10 mol %) phosphor powders calcined at 1200 °C for 2 h possess a Sr 3 Al 2 O 6 single cubic phase. The Sr 3 Al 2 O 6 :Eu 2+ , Dy 3+ crystallites show a new flower-like morphology. The excitation and emission spectra indicate that a broad excitation band chiefly lies in the visible range and that Sr 3 Al 2 O 6 :Eu 2+ , Dy 3+ phosphor powders exhibit a broad red emission band with emission peak at 612 nm under 472 nm excitation. Sr 3 Al 2 O 6 :Eu 2+ , Dy 3+ at the Eu 2+ concentration of 8 mol% shows the strongest luminescent intensity. Red long-afterglow phosphorescence is observed in the dark with naked eye after the removal of the excitation source.