Coadsorption of Hydrogen and Carbon Monoxide

It was shown [33] for uranium (U), possessing a related electronic structure ([Rn] 5f 1 ) to gadolinium ([Xe] Af 5d 6s ), that after CO adsorption two features appear one structure at 2.4 eV binding energy is due to C 2p emission from uranium carbide (UC) and the other one at 2.2 eV from U caused by the existence of oxygen. 

Due to the similar electronic structure to uranium, the peak intensities for Gd as substrate were analogously determined at 2, 2.4, and 4 eV as a function of CO 

In the following the chemical reactions will be described being induced by increasing CO exposure the superscript gas means gaseous, ads means adsorbed in any way. For a better comparison all formulae were referenced to a total of four CO molecules. 

During the first step only hydrogen is removed, no additional species are adsorbed aU products are therefore gaseous pointing to the creation of formaldehyde which can directly be created via a gas phase reaction  

The ratio of eight H atoms to fom CO molecules for the complete removal of hydrogen can independently be estimated by the following consideration. 

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In order to get a deeper insight into the coadsorption of hydrogen and carbon monoxide (CO) on gadolinium it is necessary to understand what happens when exposing the Gd surface to each single type of molecules. The behavior of hydrogen was already discussed in Sect. 4.1 the adsorption of CO will first be described in the following. 

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