As the added flux has much more severe effect on the luminescence properties

the influence of Li

2

CO

3

/(Li

2

CO

3

+K

3

PO

4

) flux ratio

x

(

x

= Li

2

CO

3

/(Li

2

CO

3

+K

3

PO

4

)) on the luminescence properties of Y

2

O

2

S:0.09Ti phosphor has been investigated to obtain the best luminescence and afterglow intensity.The composite flux of Li

2

CO

3

plus K

3

PO

4

was selected because Li

2

CO

3

and K

3

PO

4

flux have been demonstrated in previous study to improve the afterglow intensity in the beginning stage and long time stage

respectively.PL spectra and afterglow measurement were used to analyze the effect of flux ratio on the luminescence and after glow properties of Y

2

O

2

S:0.09Ti phosphor.And XRD measurements were carried out to verify the crystal structure.XRD results showed that the single phase Y

2

O

2

S:0.09Ti phosphor could be obtained when flux ratio x increases from 0 to 1.0

while the grain growth orientation may change obviously.The fact that excitation spectra are similar in all flux range demonstrates that the flux ratio has little effect on the excitation process.Nevertheless

the emission spectra showed that the intensity of emission peak at 565 nm depended greatly on the flux ratio.Luminescence intensity of Y

2

O

2

S:Ti phosphor increased with an increase of Li

2

CO

3

ratio x

then reduced as x over 0.8.On the other hand

afterglow brightness of Y

2

O

2

S:Ti was enhanced at appreciate Li

2

CO

3

/(Li

2

CO

3

+K

3

PO

4

) ratio of about 0.4 with an enhanced afterglow brightness(9.1 mcdm

-2

) at(decay) time of 30 min.This value is about four times as that of single Li

2

CO

3

doping(2.4 mcdm

-2

)

and two times as that of single K

3

PO

4

doping(4.3 mcdm

-2

).Above results about the effect of flux ratio on luminescence after glow properties could be used to adjust the overall properties of Y

2

O

2

S:0.09Ti phosphor.The best afterglow with yellow color is obtained at appreciate Li

2

CO

3

/(Li

2

CO

3

+K

3

PO

4

) ratio of about 0.4

and its afterglow can last over 5 h with recognizable intensity level(0.32 mcd/m

2

) after the removal of the excitation light.