Surface and Epitaxial Stresses on Supported Metal Clusters

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• 作者：Rémi Lazzari ; Jacek Goniakowski ; Gregory Cabailh ; Rémi Cavallotti ; Nicolas Trcera ; Pierre Lagarde ; Jacques Jupille
• 刊名：Nano Letters
• 出版年：2016
• 出版时间：April 13, 2016
• 年：2016
• 卷：16
• 期：4
• 页码：2574-2579
• 全文大小：436K
• 年卷期：0
• ISSN：1530-6992

文摘

Surface stress and energy are basic quantities in the Gibbsian formulation of the thermodynamic description of surfaces which is central in the formation and long-term behavior of materials at the nanoscale. However, their size dependence is a puzzling issue. It is even unclear whether they decrease or increase with decreasing particle size. In addition, for a given metal, estimates often span over an order of magnitude, far apart from bulk data, which, in the absence of any explicit size-dependence rule, escapes understanding. Here, we combine X-ray absorption and nanoplasmonics data with atomistic simulation to describe α-Al₂O₃(0001)-supported silver particles. By comparison to MgO(001)-supported and embedded silver, we distinguish epitaxial and surface stress. The latter is shown to dominate above 3 nm in size. Since the observation mostly relies on surface/bulk ratio, a metal-independent picture emerges that is expected to have far-reaching consequences for the understanding of the energetics of nanoparticles.