The (Y,Gd)BO 3∶Eu phosphor was synthesized by solid state reaction. The UV spectra showed that in a certain range of Gd 3+ concentration, more Gd 3+ absorbed energy and transferred it to Eu 3+ with its increasing con...The (Y,Gd)BO 3∶Eu phosphor was synthesized by solid state reaction. The UV spectra showed that in a certain range of Gd 3+ concentration, more Gd 3+ absorbed energy and transferred it to Eu 3+ with its increasing concentration. From the spectra in VUV region, it was observed that both the doping and the concentrations of Gd 3+ , Eu 3+ greatly affected the absorption of the host lattice. The absorbances at 147 nm and 170 nm increased when the Gd 3+ was doped which can be explained as that Gd 3+ transferred energy to BO 4. The optical properties of (Y,Gd)BO 3∶Eu were the best when the concentration of Eu 3+ was about 0.04.展开更多
Y, Gd)Al 3(BO 3) 4∶Eu 3+ samples were prepared by the conventional solid state reaction. The XRD results indicate that the crystal symmetry is low. The excitation spectrum is composed of two broad bands centered ...Y, Gd)Al 3(BO 3) 4∶Eu 3+ samples were prepared by the conventional solid state reaction. The XRD results indicate that the crystal symmetry is low. The excitation spectrum is composed of two broad bands centered at about 170 and 250 nm respectively. In the emission spectra, the peak wavelength is about 616 nm under 147 nm VUV excitation. The luminescent chromaticity coordinate and the relative intensity change along with Gd 3+ mole concentration in the range of 0.15 to 0.85 mol (and Eu 3+ mole concentration, 0.02 to 0.1 mol). The correlative data show that the concentration quenching occurs when the Eu 3+ mole concentration ranges from 0.02 to 0.1 mol, and the Gd 3+→Gd 3+, Gd 3+→Eu 3+ and host→Eu 3+, Gd 3+ energy transfers exist, and Gd 3+ mole concentration influences Eu 3+ emission.展开更多
The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction ...The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980～1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process.展开更多
文摘The (Y,Gd)BO 3∶Eu phosphor was synthesized by solid state reaction. The UV spectra showed that in a certain range of Gd 3+ concentration, more Gd 3+ absorbed energy and transferred it to Eu 3+ with its increasing concentration. From the spectra in VUV region, it was observed that both the doping and the concentrations of Gd 3+ , Eu 3+ greatly affected the absorption of the host lattice. The absorbances at 147 nm and 170 nm increased when the Gd 3+ was doped which can be explained as that Gd 3+ transferred energy to BO 4. The optical properties of (Y,Gd)BO 3∶Eu were the best when the concentration of Eu 3+ was about 0.04.
文摘Y, Gd)Al 3(BO 3) 4∶Eu 3+ samples were prepared by the conventional solid state reaction. The XRD results indicate that the crystal symmetry is low. The excitation spectrum is composed of two broad bands centered at about 170 and 250 nm respectively. In the emission spectra, the peak wavelength is about 616 nm under 147 nm VUV excitation. The luminescent chromaticity coordinate and the relative intensity change along with Gd 3+ mole concentration in the range of 0.15 to 0.85 mol (and Eu 3+ mole concentration, 0.02 to 0.1 mol). The correlative data show that the concentration quenching occurs when the Eu 3+ mole concentration ranges from 0.02 to 0.1 mol, and the Gd 3+→Gd 3+, Gd 3+→Eu 3+ and host→Eu 3+, Gd 3+ energy transfers exist, and Gd 3+ mole concentration influences Eu 3+ emission.
文摘The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980～1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process.
