Al掺杂四针状纳米ZnO生长机制分析

采用热物理法制备不同量Al掺杂的ZnO纳米材料,利用XRD分析掺杂前后试样的物相结构,并通过TEM鉴定粉体中的四针状纳米氧化锌（T-ZnO）结构。结果表明,Al掺杂纳米T-ZnO晶须的结晶过程是气液固（VLS）方式,晶须生长具有择优取向。透射电镜高分辨图像揭示凝固过程中晶须沿0001]轴向生长,随着时间的延长,Zn原子首先形成核心部分并向外在晶须表面呈台阶状生长,从Al液中带走部分Al原子,进而促成纳米晶须的不断伸长且直径变大。

Growth mechanism of tetrapod whiskers of Al-doped nano T-ZnO

The Al-doped nano-sized ZnO materials were synthesized by thermal physical method.Firstly,the basic structures of different samples were studied by XRD.And then,the growth mechanism of Al-doped tetrapod nano-whiskers of ZnO（T-ZnO） was investigated by selected area electron diffraction method and high resolution transmission electron microscopy.The analyses of this growth mechanism show that the process is in a gas-liquid-solid（VLS） mode.The nano sized whiskers have optimized ／ growth orientation.And most of these nano-sized whiskers have high crystal quality.The increased adulteration of Al atoms could improve the formation of nano-sized ZnO whiskers.The starting point of the growth is the nucleus part.Gradually,Zn atoms and some Al atoms form nano-sized whiskers from nucleus in a step-by-step mode.