State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Langmuir. 2011 Sep 20;27(18):11654-9. doi: 10.1021/la201889n. Epub 2011 Aug 25.
Nearly monodisperse LaAlO(3) hollow spheres are synthesized by a novel precursor thermal decomposition method. Spherical colloids of capsulelike precursors with uniform diameters of 273 ± 35 nm have been synthesized by a solvothermal method. These spherical colloids could convert to LaAlO(3) hollow spheres with diameters of 166 ± 26 nm by a thermal decomposition process. The thermal transformation process from the precursors to LaAlO(3) was characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and the Fourier transform infrared spectroscopy (FT-IR). By the doping of various lanthanide ions (Sm(3+), Eu(3+), and Tb(3+)), the emission luminescence of lanthanide-doped LaAlO(3) hollow microspheres can be tuned from red to green. In particular, these luminescent LaAlO(3) hollow spheres can be well dispersed in polar solvents such as the ethanol and water, which broadens the range of potential applications of these hollow spheres. The UV-vis absorption spectra show energy absorption at 211, 223, and 313 nm corresponding to the host lattice absorption and charge-transfer transitions. The results are in good agreement with the peaks observed in the excitation spectra.
通过一种新型的前驱体热分解方法合成了近乎单分散的 LaAlO(3) 空心球。通过溶剂热法合成了具有均匀直径 273 ± 35nm 的胶囊状前驱体的球形胶体。这些球形胶体通过热分解过程可转化为直径为 166 ± 26nm 的 LaAlO(3)空心球。前驱体到 LaAlO(3)的热转变过程通过热重分析（TGA）、X 射线衍射（XRD）和傅里叶变换红外光谱（FT-IR）进行了表征。通过掺杂各种镧系离子（Sm(3+)、Eu(3+)和 Tb(3+)），可以调节镧系掺杂 LaAlO(3)空心微球的发射发光从红色到绿色。特别是，这些发光的 LaAlO(3)空心球可以很好地分散在极性溶剂中，如乙醇和水中，这拓宽了这些空心球的潜在应用范围。紫外可见吸收光谱在 211、223 和 313nm 处显示出与主晶格吸收和电荷转移跃迁相对应的能量吸收。结果与激发光谱中观察到的峰非常吻合。
