The (Y,Gd)BO3:Tb3+ and Li+-doped (Y,Gd)BO3:Tb3+ phosphors were prepared by high temperature solid-state method. The inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), and the excitation and emission spectra were used to characterize the samples. The results of ICP-AES and XRD indicated that Li+ ions could enter the (Y,Gd)BO3:Tb3+ lattice and induce the lattice expansion. It could be seen from SEM that the particles were spherical and non-aggregated when Li+-ions were doped into (Y,Gd)BO3:Tb3+ phosphor. With the incorporation of Li+ ions into (Y,Gd)BO3:Tb3+, the excitation intensity of (Y,Gd)BO3:Tb3+ was found to increase and, thus, the emission intensity of (Y,Gd)BO3:Tb3+ increases. The optimal Li+ doping concentration of ions was found to be 0.025 mol per formula unit, which was also found to induce concentration quenching due to the increase in Tb3+ content from 10 mol.% to 12 mol.%.
Highly luminescent CdSe/ZnS nanocrystals were obtained by adapting non-TOP-based synthesis and a subsequent two-phase ZnS shelling procedure:the core CdSe nanocrystals were synthesized in sole solvent paraffin liquid with cadmium oxide,elemental sele-nium,and oleic acid; the deposition of the ZnS shell was conducted by using zinc stearate in toluene and sodium sulfide in deionized water. The green and low-cost route was proved to be more efficient to constrain the size of core nanocrystals while tuning the growth of shell particles,which results in high quantum yields of CdSe/ZnS nanocrystals. The present route is accessible to laboratories with limited synthetic expertise to create CdSe/ZnS nanocrystals and easily scaled up to industrial applications.
Ye XinyuaZhuang WeidongHu YunshengLuo XinyuZhao ChunleiHuang Xiaowei
