Synthesis and luminescence properties of novel green-emitting KPb4(PO4)3:xTb3+ phosphors

A series of phosphors KPb4 − x(PO4)3:xTb3+ (x = 0, 0.04, 0.08, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22) were prepared by solid-state reaction method. The as-prepared samples were characterized by powder X-ray diffractometer, scanning electron microscope and photoluminescence spectrometer. The emission spectra consisted of several sharp emission peaks centered at 620, 585, 544 and 489 nm, which can be assigned to the 5D4–7Fj (j = 3, 4, 5, 6) transitions of Tb3+ ions. The optimum dopant concentration of Tb3+ activator in KPb4(PO4)3 host matrix is about 16 mol%. The CIE coordinates of KPb3.84(PO4)3:0.16Tb3+ phosphor was measured to be (0.295, 0.571), corresponding to green color.