کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5425596 | 1395861 | 2006 | 14 صفحه PDF | دانلود رایگان |

Model Pt-ceria catalysts have been prepared by the evaporation of Pt onto ceria (CeO2) films grown on Si(1Â 1Â 1) substrates. Photoelectron spectroscopy (XPS, UPS) data are used to characterise the surfaces and their adsorption characteristics, and CO oxidation has been used as a probe reaction to test the activity of the model catalysts.Pure ceria is catalytically-inactive under the test conditions employed, whereas the model Pt/ceria catalysts demonstrate high activity for CO oxidation. The model catalysts also reproduce many of the characteristics of their high-surface area analogues, including the possession of a characteristic light-off temperature, hysteresis in activity as a function of temperature and a negative-order dependence on the CO partial pressure.Many aspects of the behaviour of these catalysts are shown to be a direct result of the strong adsorption of CO. The sensitivity of the dispersed Pt towards oxidation is also experimentally-demonstrated and the importance of this phenomenon is discussed.
Journal: Surface Science - Volume 600, Issue 15, 1 August 2006, Pages 3058-3071