Luminescence properties and energy transfer of co-doped Ba_3GdNa(PO_4)_3F:Ce~(3+)Jb~(3+) green-emitting phosphors

摘要

Phase pure Ce_(3+)and Tb_(3+)singly doped and Ce_(3+)/Tb_(3+)co-doped Ba~(3)GdNa(PO~(4))~(3)F samples have been synthesized via the high temperature solid-state reaction. The crystal structures, photoluminescence properties, fluorescence lifetimes, thermal properties and energy transfer of Ba~(3)GdNa(PO~(4))~(3)F:Ce_(3+),Tb_(3+)were systematically investigated. Rietveld structure refinement indicates that Ba~(3)GdNa(PO~(4))~(3)F crystallizes in a hexagonal crystal system with the space group P-6 . For the co-doped Ba~(3)GdNa(PO~(4))~(3)F:Ce_(3+),Tb_(3+)samples, the emission color can be tuned from blue to green by varying the doping concentration of the Tb_(3+)ions. The intense green emission was realized in the Ba~(3)GdNa(PO~(4))~(3)F:Ce_(3+),Tb_(3+)phosphors on the basis of the highly efficient energy transfer from Ce_(3+)to Tb_(3+). Also the energy transfer mechanism has been confirmed to be quadrupole–quadrupole interaction, which can be validated via the agreement of critical distances obtained from the concentration quenching (13.84 Å). These results show that the developed phosphors may possess potential applications in near-ultraviolet pumped white light-emitting diodes.