Roiaz Matteo, Falivene Laura, Rameshan Christoph, Cavallo Luigi, Kozlov Sergey M, Rupprechter Günther
Institute of Materials Chemistry, Technische Universität Wien, 1060 Vienna, Austria.
KAUST Catalysis Center, Kind Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
J Phys Chem C Nanomater Interfaces. 2019 Apr 4;123(13):8112-8121. doi: 10.1021/acs.jpcc.8b07668. Epub 2018 Oct 23.
Carbon monoxide participates in many copper-catalyzed reactions, which makes CO-induced structural changes of Cu catalysts key for important industrial processes. We have studied the interaction of carbon monoxide with the Cu(100) single crystal termination at 120, 200, and 300 K by means of low-energy electron diffraction (LEED), temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), polarization-modulation infrared reflection absorption spectroscopy (PM-IRAS), and density functional theory (DFT) calculations. The absorption band of CO (2082-2112 cm) at elevated gas pressure (up to 5 mbar) and at 200/300 K was found at a higher wavenumber than the characteristic band of the (2 × 2)CO structure and was consistent with CO adsorbed on low-coordinated Cu atoms. The combined PM-IRAS/DFT analysis revealed that exposure to CO induced surface roughening through the formation of Cu adatoms and clusters on the (100) terraces. The roughened surface seemed surprisingly active for CO dissociation, which indicates its unique catalytic properties.
一氧化碳参与许多铜催化的反应，这使得一氧化碳诱导的铜催化剂结构变化成为重要工业过程的关键。我们通过低能电子衍射（LEED）、程序升温脱附（TPD）、X射线光电子能谱（XPS）、偏振调制红外反射吸收光谱（PM-IRAS）和密度泛函理论（DFT）计算，研究了一氧化碳在120、200和300 K下与Cu(100)单晶表面的相互作用。在升高的气体压力（高达5毫巴）和200/300 K下，一氧化碳的吸收带（2082 - 2112厘米）出现在比(2×2)CO结构特征带更高波数处，这与吸附在低配位铜原子上的一氧化碳一致。PM-IRAS/DFT联合分析表明，暴露于一氧化碳会通过在(100)台面上形成铜原子和团簇导致表面粗糙化。粗糙化的表面对一氧化碳解离似乎具有惊人的活性，这表明其具有独特的催化性能。
