| Summary: | 碩士 === 國立虎尾科技大學 === 光電與材料科技研究所在職專班 === 101 === In this study, YVO4 was selected as the host material and doped with different concentrations of Pr3+ ions which were synthesized using solid-state reaction method. The structure, micrographics and photoluminescence properties of the synthesized phosphors were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectrophotometer, respectively.
The XRD results showed that the crystal structure of YVO4:Pr3+ phosphors calcined 1100℃for 8 hr can be attributed to the Orthorhombic structure for YVO4. The SEM images show the particles are irregular, but more uniform distribution for Pr3+ ion concentration is 0.3 mol%. The excitation spectra of YVO4:Pr3+ shows a broad excitation band in the wavelength range of 250-350 nm resulting from the charge transfer transition of Pr3+-O2-. In the wavelength region of 450-500 nm, originates from the f-f transition of 3H4-3P2 within Pr3+ 4f electron configuration. The emission spectra for YVO4:Pr3+ phosphor show that there are the 3P0→3H4, 3H5, 3H6 and 1D2→3H4 transition of Pr3+ ion under an excitation wavelength of 458 nm. The maximum emission intensity is obtained for YVO4 doped with 0.3 mol% Pr3+ ions with a CIE chromaticity coordinates of (x=0.272, y=0.188) and Rc=18.51Å.
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