LI Yan-hong, HONG Guang-yan. Synthesis and Spectra Properties of Nanocrystalline GdPO<sub>4</sub>:Eu<sup>3+</sup>[J]. Chinese Journal of Luminescence, 2005,26(5): 587-591
LI Yan-hong, HONG Guang-yan. Synthesis and Spectra Properties of Nanocrystalline GdPO<sub>4</sub>:Eu<sup>3+</sup>[J]. Chinese Journal of Luminescence, 2005,26(5): 587-591DOI:
Rare earth doped nanocrystalline phosphors have attracted great interest.The main work concerns the synthesis and the spectral changes of nanoparticles.It has been found that many gadolinium compounds doped with Eu
3+
have a higher luminous efficient due to high efficient energy transfer from Gd
3+
to Eu
3+
ions
moreover
PO
4
3+
groups show high Absorption in VUVregion
thereby
GdPO
4
:Eu
3+
could be applied to plasma display panels.Nanocrystalline GdPO
4
:Eu
3+
was prepared by co-precipitation method with EDTA-2Na.The results of XRDindicated that nanocrystalline GdPO
4
:Eu
3+
with the monoclinic monazite type was synthesized at 700 ℃
the XRDintensities of the samples increased with increasing of annealing temperature due to much better crystallization.By applying the Scherrer formula to the full width at half maximum of the(200) diffraction peak
the mean particle sizes could be calculated as 18 nm and 40 nm
for the samples annealed at 700 ℃ and 800 ℃
respectively.The TEM images of the samples show the primary crystal size to be in consistent with the mean particle size obtained from XRD.The excitation spectrum of GdPO
4
:Eu
3+
consist of several bands.The bands in the region from 200 nm to 300 nm may be due to the charge transfer band
the other bands from 300 nm to 500 nm are assigned to the Absorption band of Gd
3+
and Eu
3+
ions.The results of emission spectra exhibit all of emission peaks associated with
5
D
0
7
F
J
transition
the relative intensity order of the emission is
I
(
5
D
0
7
F
1
)
>
I
(
5
D
0
7
F
2
)
>
I
(
5
D
0
7
F
4
)
the emission intensities of the samples are increased with increasing of annealing temperature due to much better crystallization
a little broad emission peaks in smaller nanoparticles are mainly from the lattice distortion. The emission spectra under 315 nm excitation display that energy transfer exist between Gd