Journal of Physical Chemistry & Biophysics
Open Access

57-Fe Mössbauer spectroscopy on Fe-Mg-O nanocomposite particles grown by a novel chemical vapor synthesis method

4^th International Conference on Physical and Theoretical Chemistry

September 18-19, 2017 Dublin, Ireland

Werner Lottermoser, Matthias Niedermaier, Amir R Gheisi, Gerold Tippelt, Johannes Bernardi and Oliver Diwald

Salzburg University, Austria
University of Erlangen-N�¼rnberg, Germany
Vienna University of Technology, Austria

Scientific Tracks Abstracts: J Phys Chem Biophys

Abstract :

Statement of the Problem: The admixture of 3d transition metals to particles and ceramic structures of non-reducible metal oxides has given rise to a variety of functionalities used in industrial applications. However, it is not easy to control the impurity localization and the nanomaterials functional properties. Methodology & Theoretical Orientation: Powders of Fe-Mg-O nanocomposite particles have been grown using a novel chemical vapor synthesis approach which involves metalorganic precursor decomposition inside the combustion flame. After annealing in controlled gas atmosphere composition distribution functions, structure and phase stability of the obtained magnesiow�¼stite nanoparticles were measured with a combination of methods. Findings: 57-M�¶ssbauer spectroscopy measurements revealed that - depending on Fe loading and annealing temperature - either metastable and superparamagnetic solid solutions of Fe III ions in periclase MgO or phase separated mixtures of MgO and antiferromagnetic magnesioferrite MgFe2O4 nanoparticles can be obtained. Conclusion & Significance: The combination of the present hybrid combustion technique with annealing protocols emphasizes the great potential of vapor phase grown non-equilibrium solids. Applying this method, phase separation, disproportionation and the appearance of magnetic properties can be tuned intentionally. Different from their bulk counterpart, MgFe2O4 nanoparticles with identical composition and structure are superparamagnetic and are promising material components for magnetic resonance imaging (MRI) as high density information storage materials or for magneto-caloric refrigeration.

Biography :

Werner Lottermoser is a Solid State Physicist. He has completed his thesis work on neutron diffraction and magnetism of special silicates at CNRS, CENG and ILL Grenoble, France, and University of Frankfurt, Germany. He obtained qualification to become Professor after studying Single Crystal Mössbauer Spectroscopy at Salzburg University, Austria, and was working in different scientific projects granted by the Austrian Fund of Scientific Research (FWF).