Optimising synthesis conditions for long lasting SrAl2O4 phosphor

Purpose - To evaluate the effect of flux, activator and co-activator on solid state synthesis of SrAl2O4: Eu2 + , Dy3 + phosphor, where boric oxide, europium oxide and dispersium oxide were used, respectively.Design methodology approach - To optimise synthesis condition of long lasting phosphorescence SrAl2O4 phosphor, boric oxide was used as a flux. To improve relative intensity of SrAl2O4: Eu2 + phosphor, the critical concentration of Eu2 + was determined. The effect of various concentration of co-activator on afterglow properties, the effect of Dy3 + ion on the emission and excitation spectra were examined.Findings - The SrAl2O4: Eu2 + , Dy3 + phosphor powders have been synthesised by solid state reaction method. The result of XRD patterns indicated that, addition of 5 mol% B2O3 enhanced the formation of SrAl2O4 at 1,200°C. Investigation on the variation of emission intensity of different phosphors containing different amounts of Eu2 + revealed that after 6 mol% of Eu2 + concentration, quenching process occurred. Dy3 + formed trap levels and results demonstrated that increasing concentration of Dy3 + up to 5 mol% reduced the relative intensity and increased the decay time.Originality value - Using B2O3 as a flux and solid state reaction method for preparation of this phosphor is in good agreement with industrial production and make it economic, because of reduced sintering temperature.