Regensburg 2007 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 44: Poster Session II (Semiconductors; Oxides and Insulators: Adsorption, Clean Surfaces, Epitaxy and Growth; Surface Chemical Reactions and Heterogeneous Catalysis; Surface or Interface Magnetism; Solid-Liquid Interfaces; Organic, Polymeric, Biomolecular Films; Particles and Clusters; Methods: Atomic and Electronic Structure; Time-resolved Spectroscopies)
O 44.34: Poster
Mittwoch, 28. März 2007, 17:00–19:30, Poster C
Electronic structure of iron oxide nanoparticles — •Aladin Ullrich, Daniel Gyasi-Antwi, Marcus Preisinger, Michael Krispin, and Siegfried Horn — Lehrstuhl für Experimentalphysik II, Universität Augsburg, D-86135 Augsburg
We have investigated the electronic structure of nanosized iron oxide and its precursor material apo-ferritin by scanning tunnelling mircroscopy (STM) and spectroscopy (STS) as well as conductive atomic force microscopy (CAFM). The remineralization of apo-ferritin molecules resulted in core sizes varying from 3 – 7 nm depending on the filling quantity of iron. Iron oxide nanoparticles were produced by thermal treatment of remineralized apo-ferritin molecules in air. Depending on the thermal treatment we were able to prepare different phases of nanosized iron oxide resembling α-Fe2O3, γ-Fe2O3 and mixtures thereof. The electronic structure of remineralized apo-ferritin and iron oxide nanoparticles has been investigated under ambient conditions and will be compared with previous measurements performed in UHV. We show that the band gap can differ from bulk material and is dominated by surface effects.