Stabilization of novel high temperature phase yellow-emitting σ-type (Ba1−x−yEuxMgy)2P2O7 phosphors using a melt synthesis technique

Novel Eu2+-activated phosphate phosphors based on high-temperature phase σ-Ba2P2O7, which is an unstable phase at room temperature, were synthesized for the first time by a melt synthesis technique using an arc-imaging furnace. By doping Mg2+ into the host lattice, Eu2+-activated σ-Ba2P2O7 phosphors were successfully obtained in a single phase form of a hexagonal structure and the emission intensity was also effectively enhanced. The relative emission peak intensity of the σ-(Ba0.67Eu0.03Mg0.30)2P2O7 phosphor was 315% of that for the σ-(Ba0.97Eu0.03)2P2O7 phosphor. The emission color tunable from green emission with a peak at 516 nm to yellow emission with a peak at 551 nm can be achieved by controlling the Mg2+ content in the σ-(Ba0.97−yEu0.03Mgy)2P2O7 phosphors.