Surface Oxidation and Sabatier Principle

The partial pressures and temperatures leading to this high-activity state of the RuO2(110) surface in the calculations, and even the absolute TOF 

These examples underline therefore already nicely the potential relevance of surface oxidation in the reactive surroundings of oxidation catalysis. In all cases discussed so far, this had a beneficial effect on the overall catalytic performance, but detrimental effects due to the formation of an inactive oxide film are of course equally well conceivable. Such a catalyst deactivation through oxidation has, e,g, been frequently suspected in the experimental literature concerning Rh surfaces [65-67], In other cases, the catalytic activity of oxide and metal surface might be comparable, so that surface oxidation would likely remain unnoticed unless explicitly looked for by experimental techniques sensitive to the atomic scale. 

Novel experimental and theoretical approaches addressing the effect of realistic environments on surface structure and composition have significantly increased the atomic-scale understanding of the oxide formation process of late TMs over the last years. Some identified key features have been reviewed for the late 4d sequence from Ru to Ag and are summarized schematically 

A most intriguing aspect of this surface oxidation is that it proceeds via the few atomic-layer thin surface oxide structures. This thickness can be ruled by kinetics, but at Pd and Ag it even seems that there are thermodynamic conditions for which the surface oxides represent the most stable phase. In 

Dreizler RM, Gross EKU (1990) Density-Functional Theory. Springer, Berlin 

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