Development of magnetic refrigeration materials for hydrogen liquefaction using combinatorial research approach

• Applicant: Dr. Konstantin Skokov, Ph.D.
• Subject Area: Synthesis and Properties of Functional Materials ; Computer-Aided Design of Materials and Simulation of Materials Behaviour from Atomic to Microscopic Scale ; Experimental Condensed Matter Physics
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 514785069

Green hydrogen produced from renewable energy sources is one of the cornerstones for establishing a climate-neutral society and realization of its carbon neutrality. However, one of the major challenges is the storage and transportation of hydrogen: as H2 gas has a large volume, liquefaction is required to reduce the volume. The efficiency of established liquefaction methods is quite low at temperatures below 100 K, so there is an urgent need to find a new technological solution. Here, we propose a fundamentally different approach to liquefy gases using the emerging magnetic cooling technology, based on the magnetocaloric effect. With the recent progress in superconducting magnets with static magnetic fields of up to 7 – 14 T, magnetocaloric cooling at cryogenic temperatures becomes realistic, which may enable a revolution in the technology of gas liquefaction. The main bottle-neck for practical applications of cryogenic magnetic refrigeration systems is the lack of magnetic refrigeration materials with giant and reversible magnetocaloric effect in the temperature range 10-80K. Solving this problem is the current worldwide research trend and it is the main objective of the present research proposal. Current applicants at NIMS and TUDa have a rich experience in the development of magnetic and magnetocaloric materials and both teams have already collaborated in the field of magnetocaloric materials, and extensively in the field of permanent magnets, before they conceived this research proposal. We believe that the strong complementary expertise of each part will not only enable us successfully completing this proposed project but will help to revolutionize hydrogen gas liquefaction technology. In the framework of this project, assisted by machine learning, we will develop novel and sustainable magnetocaloric compounds with a giant and reversible magnetic entropy change and excellent mechanical durability. The predicted compounds with promising properties will be experimentally developed using various advanced synthesis methods from development of single crystals to powder processing, compaction and shaping methods. We will select the most promising candidates and conduct a fundamental study on the physical properties including magnetocaloric effect, resistivity, magnetostriction, elastic moduli, etc. and their microstructure in order to understand the origin of hysteresis and nature of enhanced magnetocaloric effect. At the end of the project, the developed novel RE-3d and rare-earth-free compounds will be evaluated in a real magnetic cooling system for H2 liquefaction. Although this technology is still in its infancy today, we are convinced that the joining the research activities of TUDa and NIMS teams through this project will open up broad prospects for establishing a future “hydrogen society” with eco-friendly energy production, its utilization and carbon neutrality.

• DFG Programme: Research Grants
• International Connection: Japan
• Cooperation Partner: Dr. Hossein Sepehri Amin