Zn/ZnO晶枝的制备与生长机制研究

摘要

The multi-layers zinc dendritic structures have been synthesized by heating the Zn powder in tube furnace. The sub-structure of the deposition has the similar form. Each sub-structure is formed by many regular hexagonal na-no-disc which has grown along the three crystal axis. The Zn/ZnO core-shell structure has obtained by the annealing process under oxygen ambient. The formation of the dendritic structures is decided by not only the characteristics of crystal growth kinetics,but also the het and mass transfer. The dendritic structures growth is a process of solidification heat releasing.%　　通过在管式炉中加热蒸发Zn粉的方法获得了具有层状结构的Zn晶枝沉积物，构成沉积物的子分枝也具有相同的结构和形状，每个亚微米尺寸的子分枝是由无数个规则的六角形纳米盘构成，这些纳米盘沿着三个晶轴方向蔓延生长，并且连接在一起形成了晶枝的主干和分枝。在氧气氛下退火，通过热氧化的方法形成了Zn/ZnO的核壳结构。所生长晶枝的形态不仅由结晶学和热力学性质所决定，也涉及到晶体生长的动力学，是热量和质量传输共同影响的结果。晶枝的生长是一个凝固潜热释放的过程，本文研究了Zn的晶枝生长以及ZnO螺旋位错的成核与生长机制。