[Preparation and luminescence properties of EuVO4].
The material of EuVO4 was prepared by solid state reaction, and the structure, crystal form and luminescence properties of the material were characterized by X ray diffraction spectrum, infrared spectrum analysis, excitation spectrum and emission spectrum, respectively. XRD was measured at different annealing temperature and the results indicate that V2O5 and Eu2O3 began to react around 600 degrees C, and the reaction almost finished at 700 degrees C with the component of product being EuVO4. The product is in tetragonal crystallographic structure, consistent with crystal EuVO4. So the high purity of EuVO4 was obtained and was stable at high temperature and in chemistry environment. The IR analysis shows that the V=O bond stretching vibration became weaker,and moved towards low wavelength However, the O-V-O bond of asymmetrical stretching vibration increased remarkably. We also found that the product transferred to EuVO4 after annealed at 700 degrees C. In excitation spectrum (the monitoring wavelength is 617 nm), the Eu-O charge transportation band disappeared with increasing temperature, and the strong band at 323 nm is corresponding to 7F0-5H3 transition of europium ion. And the other bands at 361, 382, 395, 417 and 465 nm are corresponding to 7F0-5D4, 7F0-5L7, 7F0-5L6, 7F0-5D3 and 7F0-5D2 transition of europium ion respectively. The excitation spectra at different annealing temperature approved the formation temperature of EuVO4 again. The emission spectra were excited at 275 nm, indicating that with the inversion of V2O5 and Eu2O3 to EuVO4, the excitation wavelength changed from 275 to 323 nm. Stimulatingly, the appearance of the bands at 467, 592 and 616 nm was corresponding to blue transition of VO4(3-) ion, magnetic dipole transition 5D0-7F1 and electric dipole transition 5D0-7F2 of europium ion at 592 and 616 nm, respectively. The authors obtained the material with both blue light and red light. And we found that VO4(3-) sensitized the luminescence intensity of europium ion remarkably.
Namila
Liaoning Key Lab of Bio-Organic Chemistry, Dalian University, Dalian 116622, China. namila@imnu.edu.cn
Wang
Xi-gui
XG
Zheng
Xue-fang
XF
Ao
Cui-hua
CH
Kang
Yi-you
YY
D005063:Europium / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D049449:Luminescence; D013050:Spectrometry, Fluorescence; D013057:Spectrum Analysis
D005456:Fluorescent Dyes; D005063:Europium