Master thesis
1. Structural investigation of chemically active oxide surfaces by surface x-ray diffraction
Topic: Oxide surfaces play a central role for the conversion of chemical into electrical energy in high temperature oxide fuel cells. Fundamental aspects of this process involving oxide surfaces are not understood, which shall be elucidated within this work on the atomic scale.
Tasks: Structural investigation of oxide surfaces using surface x-ray diffraction at synchrotron radiation facilities (ANKA (KIT Karlsruhe), PETRA III (DESY, Hamburg), ESRF (Grenoble)) and electron diffraction in a laboratory UHV system as a function of the O2 pressure and temperature. Surface composition characterisation by Auger electron spectroscopy, data evaluation using existing software.
2. Oxidation of metal nanoparticles on oxide surfaces
Topic: Metal nanoparticles play an important role as catalysts during the conversion of harmful gases (e.g. 3 way car catalyst). Often it is not clear, if the particles are more active in the oxidized or in the metallic state. As a prerequisite to answer this question the oxidation of nanoparticles needs to be understood.
Tasks: Growth of metal nanoparticles on oxide substrates by thermal evaporation, structural characterization of nanoparticles by atomic force microscopy (AFM) and in-situ x-ray diffraction during oxidation using synchrotron radiation (ANKA (KIT Karlsruhe), PETRA III (DESY, Hamburg), ESRF (Grenoble)). Analysis of the chemical composition by Auger electron spectroscopy. data evaluation using existing software.