The complexes of samarium

europium and different proportion(Eu:Gd)with 4

4

4-trifluoro-1-(2-furyl)-1

3-butanedione and 1

10-phenanthroline were synthesized in anhydrous alcohol solution.The pure or doped solid complexes of Eu(FTFA)3Phen

Sm(FTFA)

3

Phen and EuxGd1-x(FTFA)

3

Phen(x=0.1

0.3

0.4

0.7

0.9)were characterized by elemental analysis

IR spectra

EDTA titration and molar conductivity.The molar conductivity indicated that all the complexes are nonelectrolyte;IR spectra showed that the ligand coordinate(double-tooth)with RE3+ ions is through the oxygen negative ion of enolic form of FTFA and the two nitrogen atoms of 1

10-phenanthroline.The fluorescence properties of these complexes were studied in this article

the excitation spectra showed that energy absorb is higher for the ligands and the energy transfer is efficient from the ligands to the RE3+.The fluorescence emission intensity of Eu(FTFA)

3

Phen is much higher than that of Sm(FTFA)

3

Phen at the fixed experimental condition.It showed that the triplet state energy of the two ligands are higher than the excitation energy of Eu

3+

ion

thus it is possible that energy transfers from 4

4

4-trifluoro-1-(2-furyl)-1

3-butanedione and o-phenanthroline to Eu

3+

through-COO-Eu-OOC-and-N-Eu-N-bonds are more efficient.Fluorescence emission intensity of

5

D

0

→

7

F

2

transitions is the strongest among the emission spectra of the europium ion complexes

so we choose this energy transition as the research object.The results showed that the emission intensity of Eu

3+

ion can be enhanced when Eu

3+

ion is substituted by Gd

3+

ion.But the mole fraction of Gd

3+

ion influence on the fluorescence emission intensity of the rare earth complexes differently.By changing the mole fraction of Gd

3+

ion

we found that if the mole fraction of Gd

3+

ion is between 0.1 to 0.6

the complexes can get higher fluorescence intensity than that of the pure Eu

3+

system.When the mole fraction of Gd

3+

was fixed at 0.3

we got the best fluorescence intensity.This doping method can not only decrease the cost of materials

but also enhance the fluorescence intensity

so it has a bright future in practical application.