In Situ Oxidation Study of Pt(110) and Its Interaction with CO

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• 作者：Derek R. Butcher ; Michael E. Grass ; Zhenhua Zeng ; Funda Aksoy ; Hendrik Bluhm ; Wei-Xue Li ; Bongjin S. Mun ; Gabor A. Somorjai ; Zhi Liu
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：December 21, 2011
• 年：2011
• 卷：133
• 期：50
• 页码：20319-20325
• 全文大小：1007K
• 年卷期：v.133,no.50(December 21, 2011)
• ISSN：1520-5126

文摘

Many interesting structures have been observed for O₂-exposed Pt(110). These structures, along with their stability and reactivity toward CO, provide insights into catalytic processes on open Pt surfaces, which have similarities to Pt nanoparticle catalysts. In this study, we present results from ambient-pressure X-ray photoelectron spectroscopy, high-pressure scanning tunneling microscopy, and density functional theory calculations. At low oxygen pressure, only chemisorbed oxygen is observed on the Pt(110) surface. At higher pressure (0.5 Torr of O₂), nanometer-sized islands of multilayered 伪-PtO₂-like surface oxide form along with chemisorbed oxygen. Both chemisorbed oxygen and the surface oxide are removed in the presence of CO, and the rate of disappearance of the surface oxide is close to that of the chemisorbed oxygen at 270 K. The spectroscopic features of the surface oxide are similar to the oxide observed on Pt nanoparticles of a similar size, which provides us an extra incentive to revisit some single-crystal model catalyst surfaces under elevated pressure using in situ tools.