Low temperature synthesis and photoluminescence properties of Mn4+-doped La2MgTiO6 deep-red phosphor with a LiCl flux

A series of Mn4+ doped La2MgTiO6 red-emitting materials with double-perovskite structure and high efficient red emission have been successfully prepared by molten salt assisted method which LiCl acting as molten salt at a relatively low temperature. The effects of the reaction temperature and the usage amounts of LiCl on the structure and photoluminescence properties of phosphors were studied. Experimental results indicate that the synthesis temperature of the Mn4+-doped La2MgTiO6 by molten salt method is only 800 degrees C while the traditional solid phase method requires 1350 degrees C. The morphology and particle size of phosphors can be well controlled by adjusting the reaction temperature and the amount of molten salt. The thermal stability and quenching mechanism of phosphors were studied by temperature dependent emission spectra, which demonstrated that LiCl is benefit to improve the thermal stability of the Mn4+ activated La2MgTiO6 phosphors.