【摘要】 采用燃烧法制备不同离子(M:Li+,Na+,K+,Mg2+,Sr2+,Ba2+,B3+,Al3+)共掺杂的纳米Y2O3∶Eu3+粉末。系统地研究了各掺杂离子对纳米Y2O3∶Eu3+材料的结构、发光性质及其寿命的影响。比较发现,掺杂不仅可以调节纳米材料的尺寸,还可以影响材料的结晶性,尤其是后者对发光性质和荧光动力学过程,如荧光强度、电荷迁移带的位置和5D0的寿命等有重要的影响。更多还原

【Abstract】 The nanopowders of Y₂O₃∶Eu³⁺ with different co-dopants (Li⁺, Na⁺, K⁺, Mg²⁺, Sr²⁺, Ba²⁺, B³⁺ and Al³⁺) were prepared by glycine-nitrate solution combustion synthesis. Structure and luminescent properties, such as the location of charge transfer band （CT band）, fluorescent intensity and lifetime of （）⁵D₀→（）⁷F₂, were studied and compared each other. The detail contents were discussed as follows:1. The nanocrystalline Y₂O₃ were cubic in symmetry by X-ray powder diffraction （XRD） pattern. The average particle sizes estimated by Scherrer’s equation indicated that co-dopants could finely adjust the average particle size. That is, co-doping of Mg²⁺ and Al³⁺ ions decreased the combustion temperature, as a result that the size of the particles decreased. However, co-doping of Li⁺, Na⁺ and K⁺ increased the combustion temperature and the particles’ size.2. The excitation and emission spectra were measured. Compared to undoped particles, the charger transfer （CT） band exhibited blueshift in most of doped ones. For Li⁺-doped particles, the shift was 6 nm. The emission intensity varied strongly with co-dopants. Li⁺-, Na⁺-, K⁺- and Sr²⁺-doped powders had stronger brightness than undoped ones, B³⁺- and Ba²⁺-doped powders had no obvious intensity change, but Mg²⁺-and Al³⁺-doped powders had weaker brightness.3. The high-resolution emission spectra were recorded under the 266 nm laser excitation. A broader band appeared between 610 and 631 nm, which was attributed to amorphous phase. The results indicated that the co-dopants of Li⁺, Na⁺, and K⁺ can promote the crystallinity of the samples. However, the co-doping of Mg²⁺ and Al³⁺ drastically causes the structure disorder.4. The fluorescence decay curves of （）⁵D₀ of the samples were measured under the excitation of 266 nm laser. The lifetime of particles co-doped with Li⁺ and Na⁺ increased as compared to that of undoped one. However, the lifetime decreased as co-doped with other dopants. In a word, the luminescent properties, such as the location of charge transfer band （CT band）, the fluorescent intensity and lifetime of （）⁵D₀→（）⁷F₂, varied with co-dopants. It can be concluded that the variation depended on co-doping by modifying the size and crystallinity of nanoparticles. And the dependence was more strongly on the crystallinity than the particle size.更多还原