Luminescence properties of Ca 14 Mg 2 (SiO 4 ) 8 :Eu 2+ from various Eu 2+ sites for white-light-emitting diodes

Abstract Ca 14 Mg 2 (SiO 4 ) 8 :Eu 2+ phosphors were synthesized by solid-state reaction method, and their luminescence properties were investigated. In the emission spectra, several overlapping emission bands originating from various Eu 2+ sites were found. Eu 2+ in Ca 14 Mg 2 (SiO 4 ) 8 exhibits green emission around 506 nm, and the sample doped with 0.1 mol% Eu 2+ shows the strongest brightness under 365 nm excitation with the quantum efficiency of 63.6%. In the excitation spectra, strong and broad excitation bands from 250 to 450 nm were observed, which could well match with the emission wavelength of the light-emitting diode chip. The fabrication test on the InGaN chip indicates the Ca 14 Mg 2 (SiO 4 ) 8 :Eu 2+ phosphor could be promising candidate for white light-emitting diodes.