Investigation of photoluminescence in Ca9Lu(PO4)7: Tb3+, Mn2+ phosphors

Ca9Lu(PO4)7: Tb3+, Mn2+ phosphors were synthesized by the solid-state reaction method, and the luminescence properties upon VUV-UV excitation were studied. For Tb3+ activated samples, the Ca9Lu0.1(PO4)7: 0.9Tb3+ exhibits very strong emission intensity upon 147 nm excitation, and the brightness is comparable to that of the commercial Zn2SiO4:Mn2+ phosphor. For Mn2+ activated samples, wide emission band of Mn2+ is predominated at 644 nm upon 404 nm excitation. But upon 275 nm excitation, two emission bands around 467 and 644 nm are found, which could be ascribed to the host emission and Mn2+ transition, respectively. Upon 147 nm excitation, a red emission band attributed to the Mn2+4T1-6A1 transition is obtained around 646 nm. In sum, we achieve green and red emissions in Ca9Lu(PO4)7: Tb3+, Mn2+, which indicates potential applications in 3D PDPs.