Introducing Eu2+ into yellow phosphor LiBaB9O15:Ce3+, Dy3+ as blue emitting source to realize white emission

A series of Dy3+, Ce3+/Dy3+, Eu2+/Dy3+ and Ce3+/Eu2+/Dy3+ doping LiBaB9O15 (LBB) phosphors were synthesized via a high temperature solid-state method. LBB:Dy3+ cannot create light under ultraviolet radiation, however, LBB:Ce3+, Dy3+ can produce yellow emission under 295 nm excitation. The energy transfer occurs from Ce3+ to Dy3+ ions via electric dipole-dipole interaction and the critical distance is estimated to be 21.15 angstrom based on concentration quenching model. Generally, Eu2+ ion is a sensitizer to Dy3+ ion, however, there is only the emission of Eu2+ in LBB:Eu2+, Dy3+, which means there is no energy transfer from Eu2+ to Dy3+ ions. Interestingly enough, when doping Eu2+ ion into LBB:Ce3+, Dy3+, white emission can be achieved by increase the blue (350-425 nm) emission intensity. The spectral property, quantum efficiency, CIE chromaticity coordinates and thermal quenching property of LBB:Ce3+, Eu2+, Dy3+ are investigated. The results indicate that LBB:Ce3+, Eu2+, Dy3+ may be a potential application to white light emitting diodes.