The long afterglow photoluminescence materials have the particular properties storing light energy and glowing slowly at dark circumstances. That is

the materials can absorb the visible lights

store the energy

and then release the energy as the visible lights. Particularly

alkaline earth aluminates doped with rare earth ions have excellent luminescence properties such as high brightness

no radiation

safety

long duration

and environmental capability

resulting in its wide applications in many fields.In this paper

Sr

1-

x

Ba

x

Al

2

O

4

: Eu

2+

Dy

3+

(

x

=0

0.2

0.4

0.6

0.8

1.0)phosphors were synthesized in a reducing atmosphere by high temperature solid state method at 1 350 ℃ with H

3

BO

3

as flux. The phosphors were characterized by X-ray diffraction(XRD). The results showed that crystal structure of the phosphors is the monoclinic phase of SrAl

2

O

4

when

x

＜0.4 and the hexagonal phase of the BaAl

2

O

4

when

x

0.4. The lattice plane distances of the phosphors increase with the content of Ba

2+

which could be explained that Ba

2+

ion radius is bigger than that of Sr

2+

ion. The crystal lattice expands with barium ion substitution for strontium ion. Photoluminescence experiments were carried out to study luminescence properties of the phosphors under the excitation of UV. The results showed that the peak of the emission spectra shifts from 515 nm to 494 nm with the

x

changing from 0 to 1.0. The blue shift phenomenon could be explained by the crystal field effect

which is affected by different coulomb attractive forces due to Ba

2+

ion doping in the host lattice. Long afterglow properties were investigated by thermoluminescence. Thermoluminescence measurements showed that trap energy level of the SrAl

2

O

4

crystal structure is deeper than that of BaAl

2

O

4

. The afterglow decay measuring showed that the phosphors of SrAl

2

O

4

crystal structure have the more superior afterglow performance than that of BaAl

2

O

4

.