Energy transfer-induced tunable emission color and thermal quenching of Ca3Y(PO4)3: Eu2+, Mn2+ phosphor for NUV-pumped white LEDs

Abstract A series of Eu2+ doped and Eu2+/Mn2+ co-doped Ca3Y(PO4)3 phosphors have been synthesized by high temperature solid-state route. In the Eu2+-doped samples, an intense and broad green emission band is presented under the excitation of 370 nm light. Emission color changing from green to warm white light is observed when different concentrations of Mn2+ ions were introduced into the lattice of Ca3Y(PO4)3:Eu phosphor, originating from an efficient energy transfer from Eu2+ to Mn2+ ions. The energy transfer mechanism from Eu2+ to Mn2+ is demonstrated to be a quadrupole–quadrupole interaction based on the concentration quenching as well as the energy transfer efficiency of 90%. The temperature-dependent luminescence of Ca3Y(PO4)3:Eu2+,Mn2+ phosphor reveal that 52% of initial intensity can be kept at 150 °C, suggesting good thermal stability of the phosphor. Our results indicate that the Ca3Y(PO4)3:Eu2+,Mn2+ phosphor may be a potential candidate for use as near ultraviolet pumped white light-emitting diodes phosphor.