Titanium-iron alloys have proven to be particularly suitable for storing hydrogen. The GreenH2Metals joint project is now investigating how well recycled titanium-iron materials can absorb H2 and release it again when required. The project, funded by the Federal Ministry of Education and Research (BMBF) with 3.3 million euros, aims to contribute to the further development of H2 technology and the circular economy.
The research project is being coordinated by the Helmholtz-Zentrum Hereon. In addition to the Bundesanstalt für Materialforschung und -prüfung (BAM), the Rheinisch-Westfälische Technische Hochschule Aachen, the Ruhr University Bochum and the Max-Planck-Institut für Nachhaltige Materialien are also partners in the project.
Research method
Titanium-iron alloys, which have a high storage capacity for hydrogen, are to be produced much more cost-effectively from recycled materials due to the high production costs of these materials - this is the research objective of the federal government's flagship project.
Using special measuring methods, the internal structures of the materials are being analysed more closely, particularly with regard to „the role that defects in the lattice structures play in the long-term stability of the materials and their storage capacity“.
The aim is to develop prediction models that allow statements to be made about the effects of impurities on the recycling process and the material properties. The safe handling of the material, especially in powder form, will also be investigated in more detail.
How titanium-iron alloys work in H2 storage
„In addition to gaseous storage in conventional pressurised storage tanks, hydrogen can also be stored in metal compounds“, say the researchers, describing the process. „The hydrogen is absorbed by the alloy like a sponge: The H2 molecules split into individual atoms on contact with the surface, penetrate the lattice-like structure of the metal, embed themselves in gaps and defect sites and combine with the material to form so-called hydrides.“
On the one hand, the described technology is very safe – the hydrogen atoms cannot escape uncontrollably due to their bond in the metal – and on the other hand, it enables „very dense“ H2 storage. Compared to conventional H2 storage systems, both high pressure and very low temperatures can also be dispensed with. According to the researchers, the hydrogen can then be released using heat (e.g. fuel cells) if required.
You can find more information here: Wasserstoffleitprojekt GreenH2Metals
