BaAl2S4∶Eu2+ nanoparticles with a size distribution of 50—150 nm were prepared by the sol-gel method. The particles were near spherical and had an intensive green emission when they were excited at 254 nm, after cal...BaAl2S4∶Eu2+ nanoparticles with a size distribution of 50—150 nm were prepared by the sol-gel method. The particles were near spherical and had an intensive green emission when they were excited at 254 nm, after calcining at 1000 ℃ in a mixture of H2S(volume fraction 10%)+N2(volume fraction 90%) for 1.5 h. X-ray diffraction patterns indicate that BaAl2S4∶Eu2+ has a cubic structure. The emission and excitation spectra show that emission was from the 4f65d4f7 transition of the activated Eu2+. The highest photoluminescence(PL) luminance is 420 cd/m2. This study indicate that the BaAl2S4∶Eu2+ could be used as photoluminescent nanocomposite materials.展开更多
The optical properties of blue emitting BaAl2S4:Eu thin-films were studied. The emission peak is around 470 nm, whose FWHM (full width at half maximum) is 35 nm. The dielectric constant is 3.03 from transmission spect...The optical properties of blue emitting BaAl2S4:Eu thin-films were studied. The emission peak is around 470 nm, whose FWHM (full width at half maximum) is 35 nm. The dielectric constant is 3.03 from transmission spectrum, and the optical band gap is approximately 4.6 eV. It is found that the cubic phase and orthorhombic phase exist in fabricated thin-films. Furthermore, the energy band structure of BaAl2S4 : Eu thin-films from X-ray photo-electron spectra (XPS) and the absorption spectra were analyzed.展开更多
文摘BaAl2S4∶Eu2+ nanoparticles with a size distribution of 50—150 nm were prepared by the sol-gel method. The particles were near spherical and had an intensive green emission when they were excited at 254 nm, after calcining at 1000 ℃ in a mixture of H2S(volume fraction 10%)+N2(volume fraction 90%) for 1.5 h. X-ray diffraction patterns indicate that BaAl2S4∶Eu2+ has a cubic structure. The emission and excitation spectra show that emission was from the 4f65d4f7 transition of the activated Eu2+. The highest photoluminescence(PL) luminance is 420 cd/m2. This study indicate that the BaAl2S4∶Eu2+ could be used as photoluminescent nanocomposite materials.
文摘The optical properties of blue emitting BaAl2S4:Eu thin-films were studied. The emission peak is around 470 nm, whose FWHM (full width at half maximum) is 35 nm. The dielectric constant is 3.03 from transmission spectrum, and the optical band gap is approximately 4.6 eV. It is found that the cubic phase and orthorhombic phase exist in fabricated thin-films. Furthermore, the energy band structure of BaAl2S4 : Eu thin-films from X-ray photo-electron spectra (XPS) and the absorption spectra were analyzed.
