The stable and crystalline phase of pure nano- structured CeO2 was directly synthesized by flame-assisted spray pyrolysis and solid state diffusion route. Different characterization techniques, including X-ray diffrac...The stable and crystalline phase of pure nano- structured CeO2 was directly synthesized by flame-assisted spray pyrolysis and solid state diffusion route. Different characterization techniques, including X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier trans- form infrared spectroscopy （FTIR）, ultraviolet-visible （UV- Vis）, and thermo gravimetric analysis （TGA） were employed to examine the structural, morphological, optical, and thermal properties of the final product. Similarly, the comparative carbon dioxide （CO2）-sensing response of as-synthesized CeO2 nanoparticles by both routes was also reported. The CeO2 nanoparticles synthesized by solid state diffusion method exhibit good sensitivity （3.38 %） at room temperature, low operating temperature （398 K）, fast response time （32 s）, and recovery time （36 s） along with good stability.展开更多
BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（SEM） and photoluminescence properties were i...BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（SEM） and photoluminescence properties were investigated. The as-synthesized BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd^3＋ by La^3＋ and Y^3＋ ions in the host BaGdB9O16：Eu^3＋ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba（Gd,Ln）B9O16（Ln=La, Y） phosphors were promising red phosphors, which might find potential applications in near-UV excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL（compact fluorescent lamp） was also done. Energy transfer mechanism of Gd^3＋ to Eu^3＋ was also discussed in this paper.展开更多
文摘The stable and crystalline phase of pure nano- structured CeO2 was directly synthesized by flame-assisted spray pyrolysis and solid state diffusion route. Different characterization techniques, including X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier trans- form infrared spectroscopy （FTIR）, ultraviolet-visible （UV- Vis）, and thermo gravimetric analysis （TGA） were employed to examine the structural, morphological, optical, and thermal properties of the final product. Similarly, the comparative carbon dioxide （CO2）-sensing response of as-synthesized CeO2 nanoparticles by both routes was also reported. The CeO2 nanoparticles synthesized by solid state diffusion method exhibit good sensitivity （3.38 %） at room temperature, low operating temperature （398 K）, fast response time （32 s）, and recovery time （36 s） along with good stability.
基金University Grants Commission (UGC), New Delhi, for sanctioning the leave under Faculty Improvement program (FIP) to carry out this research work
文摘BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（SEM） and photoluminescence properties were investigated. The as-synthesized BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd^3＋ by La^3＋ and Y^3＋ ions in the host BaGdB9O16：Eu^3＋ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba（Gd,Ln）B9O16（Ln=La, Y） phosphors were promising red phosphors, which might find potential applications in near-UV excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL（compact fluorescent lamp） was also done. Energy transfer mechanism of Gd^3＋ to Eu^3＋ was also discussed in this paper.
