Investigation of the structural and photoluminescence properties of Eu3+ doped Na6CaP2O9 phosphors for solid state lighting

A series of Eu3+ doped Na6CaP2O9 phosphors were synthesized via conventional solid state reaction method and characterized through XRD, FTIR, diffused reflectance, photoluminescence excitation and emission spectra and Raman spectra. The XRD analyses confirm the successful synthesis of hexagonal structured Na6CaP2O9 matrix. The luminescent spectra reveal that the samples can be well excited under near UV light to get an efficient orange red emission. To get a deeper insight into the usefulness of the present material, the phonon sideband analysis and Judd- Ofelt analysis were also performed. The energy transfer interaction between Eu3+ ions was dipoledipole in nature, as evident from the Dexter theory. The thermal stability analysis and quantum yield measurements were also made. The CIE coordinates of the phosphors were observed to lie in the orange-red region. The present investigation proves the Eu3+ doped Na6CaP2O9 to be a potential orange-red phosphors in near-UV based LEDs.