| Summary: | 碩士 === 國立虎尾科技大學 === 光電與材料科技研究所 === 98 === In this study, the InVO4 doped with different Eu3+ ion concentrations had been synthesized using the sol-gel method, and the best crystallinity can be obtained for calcining at 950℃ for 6 hr in air. The thermal analysis according to the DTA-TGA curves. The InVO4 powders were heated at temperature from 650℃ to 1000℃ for various times. The InVO4 phase was formed at the beginning of 650℃.XRD results indicate that the crystallinity of InVO4:Eu3+ powders decreases with increasing Eu3+ ion concentrations. From the SEM images, the shapes of the InVO4 particles are uniform and like pebbles. With increasing Eu3+ ion concentrations, the shapes of the InVO4:Eu3+ particles become smaller and irregular. The adsorption band of InVO4 at about 326nm, the emission wavelength of green light at 530nm. In the PL studies, the sharp excitation peaks between 300 and 600 nm correspond to the Eu3+ intra-4f transitions. Excitation at 326 nm in terms of Eu3+ concentrations in (In1-xEux)VO4 powders shows that the (In1-xEux)VO4 phosphors display bright red luminescence at about 615 nm belonging to the 5D0→7F2 electric dipole transition, and the time-resolved 5D0→7F2 transition presents a single exponential decay behavior. The saturation of emission intensity excited by intra-4f transitions occurs at a concentration of x = 0.3, indicating that the concentration quenching is active when x > 0.3.
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