A novel white emitting phosphor of Dy3+ doped Ca19Mg2(PO4)14 for light-emitting diodes

A series of Dy3+ doped Ca19Mg2(PO4)14 phosphors were firstly synthesized by the solid-state reaction method. The phase purity and characteristic luminescent properties are investigated in detail by X-ray diffraction refinement, photoluminescence spectra and decay times measurement. Under 365 nm excitation, Ca19Mg2(PO4)14:Dy3+ phosphor can exhibit intense warm white emission with CIE chromaticity coordinates (0.400, 0.452) and low correlated color temperature (3994 K). The optimal doping contents of Dy3+ in Ca19Mg2(PO4)14 is determined to be 2%. The thermal quenching property of Ca19Mg2(PO4)14:Dy3+ is also investigated and it remains 60% of the initial emission intensity even when the temperature increases to 230 °C. The results show that Ca19Mg2(PO4)14:Dy3+ can be a promising single phased white emitting phosphor for UV white LEDs.