Tunable luminescence properties and efficient energy transfer in Eu2+,Mn2+ co-doped Ba2MgP4O13

A series of Ba2Mg1−xMnxP4O13 (x = 0–1.0) and Ba1.94Eu0.06Mg1−xMnxP4O13 (x = 0–0.15) phosphors were prepared by conventional solid-state reaction. X-ray powder diffraction (XRD), the photoluminescence spectra, and the decay curves are investigated. XRD analysis shows that the maximum tolerable substitution of Mn2+ for Mg is about 50 mol% in Ba2MgP4O13. Mn2+-singly doped Ba2MgP4O13 shows weak red-luminescence peaked at about 615 nm. The Eu2+/Mn2+ co-doped phosphor emits two distinctive luminescence bands: a blue one centered at 430 nm originating from Eu2+ and a broad red-emitting one peaked at 615 nm from Mn2+ ions. The luminescence of Mn2+ ions can be greatly enhanced with the co-doping of Eu2+ in Ba2MgP4O13. The efficient energy transfer from Eu2+ to Mn2+ is verified by the excitation and emission spectra together with the luminescence decay curves. The emission colors could be tuned from the blue to the red-purple and eventually to the deep red. The resonance-type energy transfer via a dipole–quadrupole interaction mechanism is supported by the decay lifetime data. The energy transfer efficiency and the critical distance are calculated and discussed. The temperature dependent luminescence spectra of the Eu2+/Mn2+ co-doped phosphor show a good thermal stability on quenching effect.