3D Atomic Arrangement at Functional Interfaces Inside Nanoparticles by Resonant High-Energy X-ray Diffraction

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• 作者：Valeri Petkov ; Binay Prasai ; Sarvjit Shastri ; Tsan-Yao Chen
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2015
• 出版时间：October 21, 2015
• 年：2015
• 卷：7
• 期：41
• 页码：23265-23277
• 全文大小：523K
• ISSN：1944-8252

文摘

With current science and technology moving rapidly into smaller scales, nanometer-sized materials, often referred to as NPs, are produced in increasing numbers and explored for numerous useful applications. Evidence is mounting, however, that useful properties of NPs can be improved further and even new NP functionality achieved by not only controlling the NP size and shape but also interfacing chemically or structurally distinct entities into single, so-called 鈥渃omposite鈥?NPs. A typical example is core鈥搒hell NPs wherein the synergy of distinct atoms at the core\shell interface endows the NPs with otherwise unachievable functionality. However, though advantageous, the concept of functional interfaces inside NPs is still pursued largely by trial-and-error. That is because it is difficut to assess the interfaces precisely at the atomic level using traditional experimental techniques and, hence, difficult to take control of. Using the core\shell interface in less than 10 nm in size Ru core鈥揚t shells NPs as an example, we demonstrate that precise knowledge of the 3D atomic arrangement at functional interfaces inside NPs can be obtained by resonant high-energy X-ray diffraction (XRD) coupled to element-specific atomic pair distribution function (PDF) analysis. On the basis of the unique structure knowledge obtained, we scrutinize the still-debatable influence of core\shell interface on the catalytic functionality of Ru core鈥揚t shell NPs, thus evidencing the usefulness of this nontraditional technique for practical applications.