An atomic-scale view of single-site Pt catalysis for low-temperature CO oxidation
An atomic-scale view of single-site Pt catalysis for low-temperature CO oxidation
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DOI：
10.1038/s41929-018-0028-2
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发表时间：
2018-03-01
期刊：
影响因子：
37.8
通讯作者：
Sykes, E. Charles H.
中科院分区：
文献类型：
--
作者：
Therrien, Andrew J.;Hensley, Alyssa J. R.;Sykes, E. Charles H.
近年来，单原子催化剂由于其高效率和节省成本而引起了极大的关注。然而，关于活性中心的性质、与载体的相互作用以及单原子催化剂的作用机制存在争议。在这里，使用相结合的表面科学和理论的方法，我们设计了一个模型系统中，我们毫不含糊地表明，个别Pt原子上的一个定义明确的Cu2O膜能够在低温下进行CO氧化。同位素标记研究表明，氧是由支持。密度泛函理论合理化的反应机制，并确认X射线光电子能谱测量的中性电荷状态的Pt。扫描隧道显微镜使可视化的活性位点作为反应的进展，和红外测量的CO伸缩频率是一致的原子分散的Pt原子。这些结果作为表征，理解和设计其他单原子催化剂的基准。
Single-atom catalysts have attracted great attention in recent years due to their high efficiencies and cost savings. However, there is debate concerning the nature of the active site, interaction with the support, and mechanism by which single-atom catalysts operate. Here, using a combined surface science and theory approach, we designed a model system in which we unambiguously show that individual Pt atoms on a well-defined Cu2O film are able to perform CO oxidation at low temperatures. Isotopic labelling studies reveal that oxygen is supplied by the support. Density functional theory rationalizes the reaction mechanism and confirms X-ray photoelectron spectroscopy measurements of the neutral charge state of Pt. Scanning tunnelling microscopy enables visualization of the active site as the reaction progresses, and infrared measurements of the CO stretch frequency are consistent with atomically dispersed Pt atoms. These results serve as a benchmark for characterizing, understanding and designing other single-atom catalysts.