New insights into the oscillatory behaviour of CO oxidation over platinum group metals
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چکیده
In this Chapter the most popular models described in the literature regarding the oscillatory behaviour of catalytic reactions such as CO oxidation are discussed. In order to explain the experimental observation introduced in Chapter 3, of oscillations between a metallic surface and a surface oxide, a new model is proposed This new model involves two key features: (1) the observation that the oxide surface gradually roughness under reaction conditions and that the metal surface gradually smoothens and (2) the relation between the surface roughness and the CO partial pressure at which the surface switches between metal and oxide (and vice versa).
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