Oxidation of Fe(110) in oxygen gas at 400 °c
2016 (English)In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 644, 172-179 p.Article in journal (Refereed) PublishedText
The initial oxidation of Fe(110) in oxygen gas at 400 °C beyond initial adsorbate structures has been studied using X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, low-energy electron diffraction, and scanning tunneling microscopy (STM). Formation of several ordered phases of surface oxides is observed at oxygen coverages between approximately 2.3 and 3.5 oxygen atoms/Fe(110) surface atom. Initially, a FeO(111)-like film is formed with a parallelogram-shaped moiré pattern. It has two mirror domains that are formed symmetrically around the growth direction of a zigzag-shaped adsorbate structure. With increased local oxygen coverage, the moiré structure transforms into a ball-shaped form. Both these moiré structures have equal atomic stacking at the surface and equal apparent height in STM, suggesting oxygen ions diffusing into the film upon oxidation and that the oxide growth takes place at the iron-iron oxide interface. The FeO(111)-like film turns into a Fe3O4(111)-like film with a triangular bistable surface termination as the oxidation proceeds further. The FeO(111)-like film growth proceeds according to the Frank-van der Merwe mechanism while the Fe3O4(111)-like film grows according to the Stranski-Krastanov mechanism.
Place, publisher, year, edition, pages
Elsevier, 2016. Vol. 644, 172-179 p.
Fe(110), Iron oxide thin film, Low-energy electron diffraction, Photoelectron spectroscopy, Scanning tunneling microscopy
Inorganic Chemistry Condensed Matter Physics
IdentifiersURN: urn:nbn:se:kth:diva-180936DOI: 10.1016/j.susc.2015.10.058ISI: 000367489000027ScopusID: 2-s2.0-84949494103OAI: oai:DiVA.org:kth-180936DiVA: diva2:897601
FunderKnut and Alice Wallenberg Foundation, Dnr 2012.0321Swedish Research Council, 621-2008-576
QC 201602052016-01-262016-01-252016-09-16Bibliographically approved