ZnO准一维纳米结构生长形态的演化机理

利用气相生长系统,通过调控实验参数,制备了多种形貌的ZnO准一维结构,如纳米条带、011-0]和21-1-0]取向的单侧生齿的梳状纳米条带、微米尺度的梳状结构，由多节状六角棱柱和八角棱柱组装成的微米条带等.通过X射线衍射、扫描电子显微镜及其所加载的能谱分析和背散射电子衍射仪、高分辨透射电子显微镜等分析技术, 对其中具有代表性的介观结构进行了系统的形貌分析和细致的结构解析.分析出基本的结构单元及其复合体, 揭示了显微尺度下ZnO晶体的外形多样性以及其形态演化中的关联和规律,即ZnO纳米条带、梳状结构和多节状微米条带具有晶体结构上的同一性.

Morphology Evolution Mechanism of ZnO Quasi-One-Dimensional Nanostructures

Controlled growth of ZnO quasi-one-dimensional nanostructures with different morphologies were accomplished by thermal oxidation of zinc vapor in a vapor deposition system. The products include uniform nanobelts with different growth directions, 011-0] and 21-1-0] orientated nanobelts with nano-teeth on one side, micro-scale comb-like nanobelts and faceted fibers with periodic junctions constructed by hexagonal prisms or octagonal prisms along 011-0] and 21-1-0] directions, and so on. The morphologies and the crystal structures were studied by X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with electron backscatter diffraction (EBSD), high-resolution transmission electron microscope (HRTEM) in details. The basic configurations constructed the multiple ZnO nanostructures were discovered, the formation mechanism and the morphology multiformity of ZnO crystals were analyzed. The evolution processes of these quasi-one-dimensional configurations were discussed based on the crystal growth mechanisms. It is found that the ZnO fibers with periodic junctions and the comb-like nanobelts have an identity of crystal structure with the nanobelts.