Structure Formation Group, INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
Langmuir. 2013 Jul 2;29(26):8427-32. doi: 10.1021/la401584z. Epub 2013 Jun 21.
The growth of nanoscale gold dendrites was studied in situ in a thin liquid film with transmission electron microscopy (TEM) using a liquid cell with silicon nitride (SiN) windows. Gold nanoparticle seeds were covered by a thin liquid layer containing precursor solution. Dendrite nucleation was induced by the electron beam leading to an initial burst of growth. The growth then settled at tip velocities between 0.1 and 2.0 nm/s for different dendrites. Tip velocities fluctuated as different dendrite geometries grew from the tips. Those dendrites showing granularities in their structure experienced the largest growth speed. Comparison of the observed velocities with diffusion-limited growth rates suggests that dendrite growth in thin films at this scale is limited by diffusion. The described method may find application in research on the mechanisms behind dendrite growth and also to study other types of anisotropic growth of nanomaterials driven by crystal and twin geometries.
采用带有氮化硅（SiN）窗口的液体池，通过透射电子显微镜（TEM）对薄液膜中的纳米金枝晶生长进行了原位研究。金纳米颗粒种子被一层含有前体溶液的薄液层覆盖。电子束诱导枝晶成核，导致初始生长爆发。然后，对于不同的枝晶，生长在尖端速度为 0.1 到 2.0nm/s 之间稳定下来。当不同的枝晶几何形状从尖端生长时，尖端速度会发生波动。那些结构呈颗粒状的枝晶经历了最大的生长速度。将观察到的速度与扩散限制的生长速率进行比较表明，在这个尺度上，薄膜中的枝晶生长受到扩散的限制。所描述的方法可能会应用于研究枝晶生长背后的机制，也可以用于研究其他类型的由晶体和孪晶几何形状驱动的纳米材料各向异性生长。
