"Iron in Functional Materials" - Symposium
Time: June 20/21, 2016
Venue: Schloss Herrenhausen, Hannover, Germany
Number of Participants: approx. 50 persons, including 20 young researchers
- Prof. Dr. Harald Behrens, Institut für Mineralogie, Leibniz Universität Hannover
- Prof. Dr. Franz Renz, Institut für Anorganische Chemie, Leibniz Universität Hannover
- Dr.-Ing. Florian Nürnberger, Institut für Werkstoffkunde, Leibniz Universität Hannover
We gratefully acknowledge VolkswagenStiftung for funding the symposium.
Iron and iron-bearing compounds are some of the most commonly used materials in our daily life. For example, consider the steel girders used to construct the office building you are working in, or the steel sheets your car was built from. Without a doubt, you have been in touch with this “classical” element several times since you got out of bed this morning. How many iron compounds can you find around you in electric motors, loudspeaker and refrigerator magnets?
While iron is still the most important metallic material, its importance in functional materials has declined. Especially for modern high-tech applications, iron has been somewhat left behind. Today, neodymium-based magnets are working in your computer’s hard disk or enabling your smartphone’s wireless communications. However, neodymium and other rare-earth metals are of limited availability in nature and their extraction often produces toxic waste that harms the environment and the people involved in their production. Recently discovered iron oxide phases could turn the tables: the laboratory-made epsilon phase of ferric iron oxide has outstanding magnetic properties that can be further improved by chemical “tuning”. This material has the potential to initiate a return to the cheap, non-toxic and omnipresent iron in high-end technical applications.
But the particular properties of iron also open doors for various new applications. In some iron compounds, the transition of spin states can be induced physically or chemically. These molecular switches are able to respond to environmental stimuli, such as light, by changing material properties, such as magnetism, electrical behavior or mechanical characteristics. Molecular switching is highly desired in various technical fields as well as in biomedicine.
In order to improve the sustainability of material use, one needs to consider the whole utilization cycle of iron. This includes the extraction of raw materials from ore deposits or steel scrap, the synthesis and characterization of new materials, the modification of engineering materials and the improvement of production procedures. Finally, it is also important to evaluate the lifetime of iron compounds by usage in technical application and in daily life, before the cycle reaches recycling and disposal, and thus connects to its start once more. This symposium will address these and further cases across different fields of research, where a renaissance of iron seems not only promising but also likely.
SEM micrographs with kind permission from Dr. Nadja Bigall, metallographical image with kind permission from the Institute for Materials Science (LUH).