Preferred structures in small particles
Preferred structures in small particles
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DOI：
10.1080/13642819508239035
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
N. Doraiswamy;L. Marks
中科院分区：
文献类型：
--
作者：
N. Doraiswamy;L. Marks
摘要：通过实时高分辨率电子显微镜观察 SiO2 负载的 Au 颗粒的形貌转变，并对数据进行定量分析，以提取不同形貌的相对概率，并与概率模型进行比较，以了解影响转变的不同参数的作用。实验数据和概率模型表现出良好的一致性，并首次揭示了一些有趣的趋势。在观察到的尺寸范围 2-8 nm 上，单晶群在二十面体多重孪生粒子 (Ic) 和十面体多重孪生粒子 (Dc) 中占主导地位。 Ic 在较小尺寸时显示出相对概率的最大值，而 Dc 概率随尺寸而增加，导致以 6·5 nm 粒径为中心的过渡区域，在该区域中 Dc 和 Ic 显示出几乎相同的相对概率。形态的活化能也受到表面应力和各向异性的影响......
Abstract Morphological transformations of Au particles supported on SiO were observed by real-time high-resolution electron microscopy, and the data were analysed quantitatively to extract the relative probabilities of the different morphologies and compared with a probability model to understand the role of the different parameters that affect the transformations. The experimental data and probability model show good agreement and reveal several interesting trends for the first time. The single crystal population dominates over the icosahedral multiply twinned particles (Ic) and the decahedral multiply twinned particles (Dc) over the observed size regime 2–8nm. The Ic shows a maximum in relative probability of occurrence at smaller sizes, whereas the Dc probability increases with size, leading to a transition region centred at 6·5 nm particle diameter at which Dc and Ic show almost equal relative probabilities. The activation energies of the morphologies are also affected by the surface stress and anisot...