Annealing Process of Anisotropic Copper Nanocrystals. 1. Cylinders
Annealing Process of Anisotropic Copper Nanocrystals. 1. Cylinders
复制标题
各向异性铜纳米晶体的退火过程。
作者：
I. Lisiecki;H. Sack;K. Weiss;J. Urban;M. Pileni
介绍了具有5重对称性(7.5×20.5 nm)的截断十面体圆柱形铜粒子的退火工艺。圆柱体的熔点低于体相的熔点。在退火过程中，发生了表面扩散、预熔和熔化的各个阶段。根据表面活性剂包覆颗粒的不同，可以观察到两种行为。当纳米晶被很好地包覆时，它们在520°C时完全消失，相反，当它们没有被很好地包覆并在预熔阶段(380°C)紧密放置在一起时，渗流过程导致形成大的聚集体，这些聚集体倾向于在远高于520°C的熔点重新结晶。
The annealing process of truncated decahedral cylindrical copper particles with 5-fold symmetry (7.5 × 20.5 nm) is presented. The melting point of the cylinders lies below the melting point of the bulk phase. During the annealing process, various stages of surface diffusion, premelting, and melting take place. Depending on the particle coating with the surfactant, two behaviors are observed. When the nanocrystals are well-coated, they disappear completely at 520 °C. At the opposite, when they are not well-coated and are placed closely together during the premelting phase (at 380 °C), a percolation process leads to the formation of large aggregates which tend to crystallize again at a melting point far above 520 °C.