The Eu

3+

-doped LaPO

4

phosphor was prepared with the conventional solid-state reaction method. Stoichiometric amounts of (NH

4

)

2

HPO

4

and H

3

BO

3

were milled and fired in air at 900℃ for 2h

and washed thoroughly with distilled water. The white powder

BPO

4

was dried at 110℃ in an oven for 3h. Stoichiometric amounts of La

2

O

3

BPO

4

Eu

2

O

3

and Li

2

CO

3

were milled and subsequently fired in air at 900℃ for 2h

and treated with 2mol·L

-1

HNO

3

and 10% NH

3

·H

2

O for 12h

washed thoroughly with distilled water. The product was dried at 110℃ in an oven for 3h

and finally stored in a desiccator until use. The Eu

3+

-doped LaPO

4

phosphor was characterized by powder X-ray diffractometry. According to our measurements with X-ray diffraction

this material belongs to monoclinic crystal system with its lattice constants:

a

=6.84Å

b

=7.08Å

c

=6.46Å

β=103.85°

it is consistent with space group

P

2

1

/

n

(No.14). The excitation and emission spectra were measured. The luminescence properties of Eu

3+

-doped LaPO

4

and energy transfer mechanism were discussed. Under 393nm radiation excitation

the emission spectra of LaPO

4

:Eu consists of the sharp line emissions in the range of 500～720nm from the transitions of electrons in 4f shell of Eu

3+

. The main peak at 612nm can be ascribed to the

5

D

0

→

7

F

2

transition of Eu

3+

it shows a strong red emission

and the

5

D

0

→

7

F

2

transition emission splits to 610

614nm. The peak at 592nm can be ascribed to the

5

D

0

→

7

F

1

transition

Eu

3+

it splits to 590

594nm also. The excitation spectra of Eu

3+

5

D

0

→

7

F

2

transition emission have two parts

the wide band between 200～300nm and sharp lines between 300～600nm. The wide band includes both charge transfer excitation of PO

4

3-

and charge transfer excitation of Eu

3+

and the sharp lines originate from Eu

3+

f-f electron transitions. The strong evidence from excitation spectra

emission spectra of this system showed that there is the energy transfer from host lattice to activator in the process of luminescence.