Spherical YAG:Ce^3+ phosphor particles with narrow size distribution were prepared by spray pyrolysis. The effects of the concentration of solution, the flow rate of cartier gas and the annexing temperature on the p...Spherical YAG:Ce^3+ phosphor particles with narrow size distribution were prepared by spray pyrolysis. The effects of the concentration of solution, the flow rate of cartier gas and the annexing temperature on the phosphor morphology were studied. The productivity of precursor particles shows a trend of drop after rising with the increase of concentration Raising the flow rate of nitrogen can improve the productivity of the precursor particles. Phosphor prepared by spray pyrolysis has obviously higher emission intensity than that synthesized by solid state reaction, spray pyrolysis makes Ce^3+ ions well distributed in the crystal lattice as the luminescent centers, and phosphor particles have regular sphericity and narrow size distribution.展开更多
TiO2@ZrO2@Y2O3 :Eu3+ composite particles with a core-multishell structure were synthesized through the combination of a layer-by-layer (LBL) self-assembly method and a sol-gel process. The obtained sam- ples were ...TiO2@ZrO2@Y2O3 :Eu3+ composite particles with a core-multishell structure were synthesized through the combination of a layer-by-layer (LBL) self-assembly method and a sol-gel process. The obtained sam- ples were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and fluorescence spectropho- tometry. The results showed that the composite particles had a core-multishell structure, spherical morphology, and a narrow size distribution. The presence of a ZrO2 layer on the TiO2 core can effec- tively prevent the reaction between the TiO2 core and a Y203 shell; the temperature for the reaction between the TiO2 core and the Y203 shell in the TiO2@ZrO2@Y2O3 :Eu core-multishell phosphor can be elevated by 300 ℃ compared to that for TiO2@ZrO2:Eu. Upon excitation of the core-multishell particles in the ultraviolet (254 nm), the Eu3+ ion in the Y2O3 :Eu3+ shell shows its characteristic red emission (611 nm, 5D0→7F2), and the photoluminescence (PL) intensity of the phosphor with the core-multishell structure was obviously greater than that of the core-shell TiO2@Y2O3 :Eu phosphor.展开更多
基金Project supported by National "The Tenth Five-Year"plan (2003BA316A01-03-05) and "The Tenth Five-Year"Plan(BE2004021) of Jiangsu provicce
文摘Spherical YAG:Ce^3+ phosphor particles with narrow size distribution were prepared by spray pyrolysis. The effects of the concentration of solution, the flow rate of cartier gas and the annexing temperature on the phosphor morphology were studied. The productivity of precursor particles shows a trend of drop after rising with the increase of concentration Raising the flow rate of nitrogen can improve the productivity of the precursor particles. Phosphor prepared by spray pyrolysis has obviously higher emission intensity than that synthesized by solid state reaction, spray pyrolysis makes Ce^3+ ions well distributed in the crystal lattice as the luminescent centers, and phosphor particles have regular sphericity and narrow size distribution.
基金supported by the National Natural Science Foundations of China(21141001,51272151)by the Fundamental Research Funds for the Central Universities(GK20111004)
文摘TiO2@ZrO2@Y2O3 :Eu3+ composite particles with a core-multishell structure were synthesized through the combination of a layer-by-layer (LBL) self-assembly method and a sol-gel process. The obtained sam- ples were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and fluorescence spectropho- tometry. The results showed that the composite particles had a core-multishell structure, spherical morphology, and a narrow size distribution. The presence of a ZrO2 layer on the TiO2 core can effec- tively prevent the reaction between the TiO2 core and a Y203 shell; the temperature for the reaction between the TiO2 core and the Y203 shell in the TiO2@ZrO2@Y2O3 :Eu core-multishell phosphor can be elevated by 300 ℃ compared to that for TiO2@ZrO2:Eu. Upon excitation of the core-multishell particles in the ultraviolet (254 nm), the Eu3+ ion in the Y2O3 :Eu3+ shell shows its characteristic red emission (611 nm, 5D0→7F2), and the photoluminescence (PL) intensity of the phosphor with the core-multishell structure was obviously greater than that of the core-shell TiO2@Y2O3 :Eu phosphor.