Structural and luminescence properties of red-emitting Cs1−xMgPO4:xEu2+ phosphors for near-UV-pumped light emitting diodes

Abstract

A series of luminescent phosphate phosphors Cs_1−xMgPO₄:xEu²⁺ were synthesized via a high temperature solid-state reaction. The phase structure and photoluminescence (PL) properties, as well as the PL thermal stability of Cs_0.96MgPO₄:0.04Eu²⁺ were investigated to characterize the resulting sample. The crystal structure and chemical composition of the Cs_0.96MgPO₄:0.04Eu²⁺ phosphor were analyzed based on the Rietveld refinements and the crystal chemistry rules, respectively. The optimum concentration of Eu²⁺ in the CsMgPO₄ phosphor was about 4 mol% and the concentration quenching effect can be attributed to the dipole–dipole interaction. This phosphor shows a broad red emission band ranging from 500 to 800 nm under the 410 nm light excitation. The above results indicate that Cs_1−xMgPO₄:xEu²⁺ phosphors have potential applications for near UV-excited w-LEDs.