Infrared Reflection Absorption Study of Carbon Monoxide Adsorbed on Submonolayer Fe-Covered Cu(100), (110), and (111) Bimetallic Surfaces
Infrared Reflection Absorption Study of Carbon Monoxide Adsorbed on Submonolayer Fe-Covered Cu(100), (110), and (111) Bimetallic Surfaces
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DOI：
10.1021/jp026212v
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发表时间：
2003-03
影响因子：
3.3
通讯作者：
T. Wadayama;K. Kubo;T. Yamashita;T. Tanabe;A. Hatta
中科院分区：
文献类型：
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作者：
T. Wadayama;K. Kubo;T. Yamashita;T. Tanabe;A. Hatta
用红外反射吸收光谱(IRRAS)研究了90K下CO在亚单层Fe覆盖的Cu(100)、(110)和(111)表面上的吸附。CO在0.3单分子层厚的Fe/Cu111双金属表面上的饱和吸附分别由于在未覆盖的铜和沉积的Fe上的吸附而在2 0 75和2 0 5 cm-1处产生两个C−O拉伸带.前者与清洁表面上的C-−-O拉伸带在频率上一致，表明沉积的Fe对铜表面没有影响。而在0.3-ML Fe/Cu(10 0)表面上，由于CO吸附在未覆盖的铜表面上，在2 10 4 cm-1处出现了一个额外的C−O伸缩带(2 0 90 cm-1).这一能带是由于沉积的Fe原子和衬底铜原子混合而形成的CO与铜原子结合形成的。在0.3mLFe/Cu(110)面上发生了更强烈的Fe-−-Cu混合；对于饱和吸附，在210 nm处观察到了相应的吸收带.
Carbon monoxide (CO) adsorption at 90 K on Cu(100), (110), and (111) covered with submonolayer Fe at room temperature has been investigated using infrared reflection absorption spectroscopy (IRRAS). Saturated adsorption of CO on the 0.3-monolayer (ML)-thick Fe/Cu(111) bimetallic surface yields two C−O stretch bands at 2075 and 2015 cm-1 due to adsorption on the uncovered Cu and on deposited Fe, respectively. The former band agrees in frequency with the C−O stretch band on the clean Cu(111) surface, indicating that the deposited Fe does not affect the Cu surface. In contrast, on the 0.3-ML Fe/Cu(100) surface, an additional C−O stretch band emerges at 2104 cm-1 on the high-frequency side of the band (2090 cm-1) due to CO adsorbed on the uncovered Cu surface. This band arises from CO bound to Cu atoms formed by intermixing of the deposited Fe and substrate Cu atoms. Even more intense Fe−Cu intermixing occurs on the 0.3-ML Fe/Cu(110) surface; for saturated adsorption, the corresponding band is observed at 210...