Dong L, Liu Y C, Tong Y H, Xiao Z Y, Zhang J Y, Lu Y M, Shen D Z, Fan X W
Key Laboratory of Excited State Processes, Chinese Academy of Sciences, Changchun Institute of Optics, Fine Mechanics and Physics, No. 16 Eastern South-Lake Road, Changchun 130033, People's Republic of China.
J Colloid Interface Sci. 2005 Mar 15;283(2):380-4. doi: 10.1016/j.jcis.2004.09.044.
Colloidal ZnO particles with narrow size distribution were prepared via a sol-gel process by base-catalyzed hydrolysis of zinc acetate. The morphology of ordered arrays of the particles was recorded by SEM. SEM also reveals that these uniform particles were composed of tiny ZnO subunits (singlets) sized of several nanometers. The size of the singlets, which is confirmed by X-ray diffraction and UV-vis absorption spectra, increases as the aging time is prolonged. The size-selective formation of colloids by aggregation of nanosized subunits is proposed to consist of two-stage growth by nucleation of nanosized crystalline primary particles and their subsequent aggregation into polycrystalline secondary colloids. The aggregates are all spherical because the internal rearrangement processes are fast enough. The ZnO colloids, i.e., the aggregates, tend to self-assemble into well-ordered hexagonal close-packed structures. Room-temperature photoluminescence was characterized for green and aged ZnO.
通过醋酸锌的碱催化水解，采用溶胶 - 凝胶法制备了粒径分布窄的胶体氧化锌颗粒。通过扫描电子显微镜（SEM）记录了颗粒有序阵列的形态。SEM还显示这些均匀的颗粒由尺寸为几纳米的微小氧化锌亚基（单重态）组成。通过X射线衍射和紫外 - 可见吸收光谱证实，随着老化时间的延长，单重态的尺寸增大。由纳米级亚基聚集形成胶体的尺寸选择性形成过程被认为包括两个阶段的生长：纳米级结晶初级颗粒的成核及其随后聚集成多晶二级胶体。由于内部重排过程足够快，聚集体均为球形。氧化锌胶体，即聚集体，倾向于自组装成有序的六方密堆积结构。对绿色和老化的氧化锌进行了室温光致发光表征。
