LAUSR

Abstract In this study, a series of Sr8MgGa(PO4)7:Eu2+ (SMGP:Eu2+) phosphors are prepared by a solid state reaction. The phase purity, crystal structure, luminescence properties, decay lifetime as well as thermal quenching and CIE chromaticity coordinates are thoroughly investigated. The as-synthesized SMGP:Eu2+ phosphors demonstrate a broad absorption band extending from 250 to 500 nm, which could be excited at near UV or blue chips. The composition-optimized SMGP:1%Eu2+ phosphor exhibit intense yellow emission at 590 nm with a FWHM (Full Width at Half Maximum) of 82 nm under 396 nm excitation. Performed DFT calculations of SMGP host and SMGP:Eu2+ phosphors explained the process of creating valence and conductivity bands, The calculated bandgaps are consistent with determined from reflectance measurements. In addition, we fabricate white light emitting devices (WLEDs) by integrating the yellow-emitting SMGP:Eu2+ phosphor, commercial blue-emitting BaMgAl10O17:Eu2+ (BAM) phosphor and a 380 nm near UV chip, which displayed excellent white light described by CIE chromaticity coordinates at (0.30, 0.31), high CRI (Ra = 91) and CCT (7129 K). The results convincingly indicate that SMGP:1%Eu2+ is an efficient yellow-emitting phosphor for WLEDs applications.