Synthesis and warm white emission performance of single-component Ca7Mg2(PO4)6:Dy3+, Eu3+phosphor for white light-emitting diodes

A single -component Ca7Mg2(PO4)6:Dy3+, Eu3+ white -emitting phosphor was synthesized by a sol-gel approach. The effects of the amounts of Dy3+ ions and Eu3+ ions on the luminescence characteristics and crystal structure of Ca7Mg2(PO4)6:Dy3+, Eu3+ were systematically investigated. The Ca7Mg2(PO4)6:Dy3+, Eu3+ phosphors had a Ca7Mg2(PO4)6 structure with an R3c (161) space group. The Ca7Mg2(PO4)6:Dy3+ phosphor showed emission peaks at both 484 nm (blue) and 576 nm (yellow), which led to the realization of white light. Furthermore, after codoping Eu3+ ions into the structure, a red emission peak (-617 nm) appeared in the spectrum as a supplementary red component. A warm white light with a low correlated colour temperature (CCT) is obtained from Dy3+/Eu3+-codoped Ca7Mg2(PO4)6. The luminescence intensity at 483 K still reaches more than 73 % of that at 303 K. The packaged LEDs display a bright warm white light with CCT value and colour rendering index (CRI) of 3878 K and 86.7, respectively, which is comfortable for the human eye. With excellent luminescence performances, the white -emitting Ca7Mg2(PO4)6:Dy3+, Eu3+ phosphor had a significant application potential in the wLED field.