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Sr1-xBaxAl2O4∶Eu2+ phosphors were synthesized in a reducing atmosphere by high temperature solid state method at 1 350 ℃.The patterns of XRD indicated that the crystal structure of the phosphors are the monoclinic phase of SrAl2O4 when x0.4 and the simple hexagonal phase of BaAl2O4 when x≥0.4 because of crystal lattice expands with Ba2+ ion substitution for Sr2+ ion.Photoluminescence experiments were carried out to study the luminescence properties of the phosphors excited under 360 nm.The results showed that emission spectra gradually changed from single green emission(λmax=516 nm) to blue-green dual-emission(λmax1= 441 nm,λmax2=486 nm) with the increase of x. When x was 0.5,there was a better property in Sr0.5Ba0.5Al2O4∶Eu2+.From the relationship between the concentration of Eu2+ ion and the intensities of emissions in Sr0.5Ba0.5Al2O4∶y%Eu2+,we get that the maximum dual-emission intensity when y=0.29%.There exist a concentration quenching effect in Sr0.5Ba0.5Al2O4∶Eu2+, and the study points out that the mechanism of concentration quenching effect is electric dipole-dipole interaction.

The Ca4Y6O(SiO4)6∶Dy3+ phosphor was synthesized by high temperature solid state reaction,and the luminescent properties were investigated.The XRD patterns indicated that the phosphor of Ca4Y6O(SiO4)6∶Dy3+ was pure crystalline phase.The study on the luminescent properties showed that the phosphor exhibits two emission bands centering at 480 nm and 573 nm.The excitation spectra for blue emission(480 nm) and yellow emission(573 nm) both have several sharp peaks,locating at 293,323,348,363,386,424,452 nm,which are assigned to the typical transitions of Dy3+.The strongest peak appears at 348 nm.The influence of the doped concentration of Dy3+ on the ratio of yellow to blue emission intensity(IY/IB),with the emission color coordinates and color temperature of phosphor Ca4Y6O(SiO4)6∶Dy3+ were studied.The effect of Dy3+ concentration on the luminescence and the quen-ching mechanism according to the Dexter theory were also analyzed.