Oxidation Inhibition of Ultrathin Fe/Pt(100) Surfaces at Room Temperature

Abstract

The oxidation and reduction of iron thin films deposited on Pt(100) surfaces were investigated by using X-ray photoelectron spectroscopy (XPS). Upon an oxygen exposure of 300 Langmuir at room temperature, top layers of a 7.5-monolayer (ML) Fe film were oxidized as Fe3O4. However, there was almost no oxidation for a 2.5-ML Fe film. On heating the films with low Fe coverages, oxygen desorption is followed by intermixing between the Fe adatoms and the Pt substrate. For the 7.5-ML Fe film, some of the oxygen atoms from the decomposed oxides are not desorbed from the surface at temperatures up to 1030 K.