11 research outputs found
Formation of patchy surface overlayers: Alkali adsorption and alkali carbon monoxide and oxygen coadsorption on Ru(0001) and Ru(10�10)
Formation of patchy surface overlayers alkali adsorption and alkali carbon monoxide and oxygen coadsorption on Ru (0001) and Ru
Unexpected Behaviour of the Surface Composition of PtRh Alloys During Chemical Reaction
The changes in the surface composition of a Pt50Rh50(100) alloy due to an ongoing 2H2 + O2f2H2O chemical reaction have been studied in situ. Exploiting the high-energy resolution and surface sensitivity of synchrotron radiation core-level spectroscopy it was possible to monitor the population of the two transitions metals atoms at the gas-surface interface. Sequences of fast high-resolution core-level spectra of the Rh3d5/2, Pt4f7/2, and O1s core levels showed a continuous exchange of atoms between the first and subsurface layers. An unexpected Pt surface enrichement was found under slightly oxidizing conditions, opposite to what found in a highly oxidizing atmosphere