Effect of Al/Sr Ratio on Properties of Strontium Aluminate Long Lasting Phosphor

The relation between properties of strontium aluminate phosphor and Al/Sr ratio was investigated.A series of strontium aluminate phosphors with different Al/Sr ratios from 1.0 to 12.0 were synthesized by solid-state method.The samples were characterized by X-ray diffraction and photoluminescence spectra.The results reveal that single phases of SrAl2O4:Eu2+,Dy3+,Sr4Al14O25:Eu2+,Dy3+ and SrAl12O19:Eu2+,Dy3+ are obtained with Al/Sr ratios of 2.0,3.5 and 10.0 respectively.When Al/Sr selects other values,the final products are mixture.Moreover,the emission spectra of the samples shift to blue-ultraviolet short wavelength from yellow-green long wave with the increase of Al/Sr ratios,which result from change of products' composition.