AVS 64th International Symposium & Exhibition
    Thin Films Division Thursday Sessions
       Session TF+SE-ThM

Paper TF+SE-ThM12
Surface Termination of Fe3O4(111) Films Studied by CO Adsorption

Thursday, November 2, 2017, 11:40 am, Room 20

Session: Control, Characterization, and Modeling of Thin Films I
Presenter: Francesca Mirabella, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
Authors: F. Mirabella, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
E. Zaki, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
F. Ivars, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
S. Shaikhutdinov, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
H.-J. Freund, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Germany
X. Li, Humboldt Universität zu Berlin, Germany
J. Paier, Humboldt Universität zu Berlin, Germany
J. Sauer, Humboldt Universität zu Berlin, Germany
Correspondent: Click to Email
Although the (111) surface of Fe3O4 (magnetite) has been investigated for more than twenty years, substantial controversy remains in the literature regarding the surface termination [1, 2]. To shed more light on this issue, we performed CO adsorption studies on (111) and (001) oriented thin films, using in-situ infrared reflection absorption spectroscopy, temperature programmed desorption, and scanning tunneling microscopy. The experimental results were rationalized on the basis of theoretical calculations, thus leading to a unified picture in which the Fe3O4(111) surface is terminated by 1/4 monolayer of tetrahedrally coordinated Fe3+ ions on top of a close-packed oxygen layer as previously determined by low energy electron diffraction. However, surface defects play a crucial role in adsorption properties and most likely dominate chemical reactions on Fe3O4(111) when exposed to the ambient.

[1] Weiss, W. and W. Ranke, Surface chemistry and catalysis on well-defined epitaxial iron-oxide layers. Progress in Surface Science, 2002. 70(1-3): p. 1-151.

[2]Parkinson, G.S., Iron oxide surfaces. Surface Science Reports, 2016. 71(1): p. 272-365.