Initial stages of Cu3Au(111) oxidation: oxygen induced Cu segregation and the protective Au layer profile
Initial stages of Cu3Au(111) oxidation: oxygen induced Cu segregation and the protective Au layer profile
复制标题
Cu3Au(111) 氧化的初始阶段：氧诱导的 Cu 偏析和保护性 Au 层轮廓
DOI：
10.1039/c3cp54709d
复制
发表时间：
2014
影响因子：
3.3
通讯作者：
H. Kasai
中科院分区：
文献类型：
--
作者：
Y. Tsuda;K. Oka;T. Makino;M. Okada;W.A. Dino;M. Hashinokuchi;A.Yoshigoe;Y. Teraoka;H. Kasai
我们报告了我们的实验和理论研究结果的Au浓度分布的Cu 3 Au（111）在高温O2分子束在室温下，使用X射线光电子能谱（XPS），结合同步辐射（SR）和密度泛函理论（DFT）。在O2暴露之前，我们观察到强烈的Au偏析到顶层，即，Au表面富集的洁净表面。我们还观察到一个逐渐的Cu表面富集，和Au富集的第二和第三（次表面）层，随着O覆盖度的增加。在0.5 ML O表面覆盖度下，Cu完全偏析到表面。富Au的第二层和第三层的氧化表面证明了保护层的形成，防止氧化深入到体内。
We report results of our experimental and theoretical studies on the Au concentration profile of Cu3Au(111) during oxidation by a hyperthermal O2 molecular beam at room temperature, using X-ray photoemission spectroscopy (XPS), in conjunction with synchrotron radiation (SR), and density functional theory (DFT). Before O2 exposure, we observe strong Au segregation to the top layer, i.e., Au surface enrichment of the clean surface. We also observe a gradual Cu surface enrichment, and Au enrichment of the second and third (subsurface) layers, with increasing O coverage. Complete Cu segregation to the surface occurs at 0.5 ML O surface coverage. The Au-rich second and third layers of the oxidized surface demonstrate the protective layer formation against oxidation deeper into the bulk.