Eu3＋-doped （Y,Gd）NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to t...Eu3＋-doped （Y,Gd）NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3＋ ions and neighboring oxygen anions. A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3＋ ions. The highest luminance for Y1-x-yGdyNbO4：Eux3＋ under 254 nm excitation was achieved at Eu3＋ concentration of 18 mol.% （x=0.18） and Gd3＋ concentration of 8.2 mol.% （y=0.082）. The luminance of Y0.738Gd0.082NbO4：Eu3＋0.18 was higher than that of a typical commercial phosphor Y2O3：Eu3＋ and the CIE chromaticity coordinate was （0.6490, 0.3506）, which was deeper than that of Y2O3：Eu3＋. The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8 μm with uniform size distribution of particles was obtained.展开更多
In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All ...In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All the samples were synthesized by high-temperature combustion method. The X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy characterization confirms the formation of pure α-phase with crystallized in orthorhombic structure of samples. The PL emission spectra of all samples exhibit characteristic green emission peaks of Tb^3＋ where the peak at 545 nm has the highest emission intensity for Tb^3＋ con- centration of 5.0 mol%. The TL glow curves of β-irradiated Tb^3＋-doped α-Sr2P2O7 phosphors were recorded at different heating rates of 2, 4, and 6 K.s^-1. TL curves of all sample exhibit combination of two peaks： peak at 420 K shifts toward higher 525 K remains unaffected temperature, while peak at with the increase in Tb^3＋ concentration as well as fading effect. The activation energy and kinetic parameters of the samples were evaluated using thermoluminescence peak shape method.展开更多
基金supported by the Chung-Ang University Research Scholarship Grants in 2008 (Sung Hwan Choi)
文摘Eu3＋-doped （Y,Gd）NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3＋ ions and neighboring oxygen anions. A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3＋ ions. The highest luminance for Y1-x-yGdyNbO4：Eux3＋ under 254 nm excitation was achieved at Eu3＋ concentration of 18 mol.% （x=0.18） and Gd3＋ concentration of 8.2 mol.% （y=0.082）. The luminance of Y0.738Gd0.082NbO4：Eu3＋0.18 was higher than that of a typical commercial phosphor Y2O3：Eu3＋ and the CIE chromaticity coordinate was （0.6490, 0.3506）, which was deeper than that of Y2O3：Eu3＋. The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8 μm with uniform size distribution of particles was obtained.
文摘In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All the samples were synthesized by high-temperature combustion method. The X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy characterization confirms the formation of pure α-phase with crystallized in orthorhombic structure of samples. The PL emission spectra of all samples exhibit characteristic green emission peaks of Tb^3＋ where the peak at 545 nm has the highest emission intensity for Tb^3＋ con- centration of 5.0 mol%. The TL glow curves of β-irradiated Tb^3＋-doped α-Sr2P2O7 phosphors were recorded at different heating rates of 2, 4, and 6 K.s^-1. TL curves of all sample exhibit combination of two peaks： peak at 420 K shifts toward higher 525 K remains unaffected temperature, while peak at with the increase in Tb^3＋ concentration as well as fading effect. The activation energy and kinetic parameters of the samples were evaluated using thermoluminescence peak shape method.
