LAUSR

Abstract Sr 2 Si 1- x Al x O 4 :Eu 2+ and Sr 2 Si 1- y P y O 4 :Eu 2+ with Al 3+ /P 5+ ions partial substitution were prepared using a solid-state reaction method. The effects of Al 3+ /P 5+ substitution on both structure and luminescence properties of Sr 2 SiO 4 :Eu 2+ was investigated. A standard Sr 2 SiO 4 structure was observed in the X-ray diffraction spectra of the Sr 2 Si 1- x Al x O 4 :Eu 2+ and Sr 2 Si 1- y P y O 4 :Eu 2+ samples. Some diffraction peaks, however, were changed after Al 3+ /P 5+ ions substitution due to the different ion radius. Upon excitation with 367 nm wavelength, all phosphor samples exhibit a broad emission band ranging from 420 nm to 680 nm, which is attributed to the 4f 6 5d 1 →4f 7 transition of the Eu 2+ ions. The luminescence intensity of Sr 2 Si 0.92 Al 0.08 O 4 :Eu 2+ and Sr 2 Si 0.94 P 0.06 O 4 :Eu 2+ is 1.55 and 1.38 times higher, respectively, than that of Sr 2 SiO 4 :Eu 2+ . In addition, the luminescence lifetime of the Sr 2 SiO 4 :Eu 2+ was also prolonged significantly by the introduction of Al 3+ and P 5+ ions. Overall, the results indicated that the application of Sr 2 SiO 4 :Eu 2+ phosphors was effectively enhanced by Al 3+ /P 5+ partial substitution in white light emitting diodes.