The Eu 2＋ /Tb 3＋ /Sm 3＋ co-doped oxyfluoride glass ceramics containing Ba2LaF7 nanocrystals are prepared in the reducing atmosphere.The X-ray difiraction results show that Eu 2＋ ,Tb 3＋ and Sm 3＋ ions are enriche...The Eu 2＋ /Tb 3＋ /Sm 3＋ co-doped oxyfluoride glass ceramics containing Ba2LaF7 nanocrystals are prepared in the reducing atmosphere.The X-ray difiraction results show that Eu 2＋ ,Tb 3＋ and Sm 3＋ ions are enriched into the precipitated Ba2LaF7 nanophase after the annealing process.It deduces efficient energy transfers from Eu 2＋ to Tb 3＋ and Sm 3＋ and intenses warm white luminescence of the glass ceramics. Comparing with the glass,the luminescence quantum yield of the glass ceramics is also enlarged by about 3 times.This demonstrates the potential white light-emitting diode application of the glass ceramics produced in this letter.展开更多
The Ce^3＋and Dy3＋ co-doped fluorosilicate glass and glass ceramics containing SrF2 or CeF3 nanocrystals were prepared under reducing atmosphere. The precipitated nano-crystalline phase shifted from cubic SrF2 to hex...The Ce^3＋and Dy3＋ co-doped fluorosilicate glass and glass ceramics containing SrF2 or CeF3 nanocrystals were prepared under reducing atmosphere. The precipitated nano-crystalline phase shifted from cubic SrF2 to hexagonal CeF3 gradually with the heat treatment temperature increasing flom 620 to 680 ℃. The glass and glass ceramics emitted white light, deriving from a combination of the Ce3＋ blue and the Dy3＋ yellow light. The CIE coordinates could be tuned by adjusting the ratio of Ce3＋/Dy3＋ concentration. The luminescence could be enhanced significantly by annealing the samples at the temperatures lower than 640℃.展开更多
Ce^(3+)and Dy^(3+)co-doped oxyfluoride glasses and glass ceramics containing CeF3 nanocrystals are prepared in a reducing atmosphere.XRD measurements and the calculated lattice parameters suggest that Dy^(3+)ions are ...Ce^(3+)and Dy^(3+)co-doped oxyfluoride glasses and glass ceramics containing CeF3 nanocrystals are prepared in a reducing atmosphere.XRD measurements and the calculated lattice parameters suggest that Dy^(3+)ions are incorporated with precipitated CeF3 nanocrystals along with a rise in the Dy^(3+)concentration or an increase in the annealing temperature.The glass ceramics emit white light close to the CIE coordinates of(0.3,0.3),derived from a combination of Ce^(3+)and Dy^(3+)emission.The CIE chromaticity coordinates of the Ce^(3+)and Dya+codoped glass ceramics can be tuned by varying the ratio of Ce^(3+)/Dy^(3+),while the luminescence intensity can be enhanced by heat treatment above 620℃.展开更多
基金supported by the National Nature Science Foundation of China(No.50902120)the Research Fund of the Doctoral Program of Higher Education of China(No.20100101120025)+1 种基金the Science and Technology Innovative Research Team of Zhejiang Province(No.2009 R50010)the Program for Changjiang Scholars and Innovative Research Team in the University
文摘The Eu 2＋ /Tb 3＋ /Sm 3＋ co-doped oxyfluoride glass ceramics containing Ba2LaF7 nanocrystals are prepared in the reducing atmosphere.The X-ray difiraction results show that Eu 2＋ ,Tb 3＋ and Sm 3＋ ions are enriched into the precipitated Ba2LaF7 nanophase after the annealing process.It deduces efficient energy transfers from Eu 2＋ to Tb 3＋ and Sm 3＋ and intenses warm white luminescence of the glass ceramics. Comparing with the glass,the luminescence quantum yield of the glass ceramics is also enlarged by about 3 times.This demonstrates the potential white light-emitting diode application of the glass ceramics produced in this letter.
基金Project supported by National Natural Science Foundation of China (50902120)the Research Fund of the Doctoral Program of Higher Education of China (20100101120025)+1 种基金the Science and Technology Innovative Research Team of Zhejiang Province (2009 R50010)Program for Changjiang Scholars and Innovative Research Team in University
文摘The Ce^3＋and Dy3＋ co-doped fluorosilicate glass and glass ceramics containing SrF2 or CeF3 nanocrystals were prepared under reducing atmosphere. The precipitated nano-crystalline phase shifted from cubic SrF2 to hexagonal CeF3 gradually with the heat treatment temperature increasing flom 620 to 680 ℃. The glass and glass ceramics emitted white light, deriving from a combination of the Ce3＋ blue and the Dy3＋ yellow light. The CIE coordinates could be tuned by adjusting the ratio of Ce3＋/Dy3＋ concentration. The luminescence could be enhanced significantly by annealing the samples at the temperatures lower than 640℃.
基金Supported by the National Natural Science Foundation of China(No 50902120)the Research Fund of the Doctoral Program of Higher Education of China(No 20100101120025)+1 种基金Science and Technology Innovative Research Team of Zhejiang Province(No 2009 R50010)Program for Changjiang Scholars and Innovative Research Team in University.
文摘Ce^(3+)and Dy^(3+)co-doped oxyfluoride glasses and glass ceramics containing CeF3 nanocrystals are prepared in a reducing atmosphere.XRD measurements and the calculated lattice parameters suggest that Dy^(3+)ions are incorporated with precipitated CeF3 nanocrystals along with a rise in the Dy^(3+)concentration or an increase in the annealing temperature.The glass ceramics emit white light close to the CIE coordinates of(0.3,0.3),derived from a combination of Ce^(3+)and Dy^(3+)emission.The CIE chromaticity coordinates of the Ce^(3+)and Dya+codoped glass ceramics can be tuned by varying the ratio of Ce^(3+)/Dy^(3+),while the luminescence intensity can be enhanced by heat treatment above 620℃.
