About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Alloys and Compounds for Thermoelectric and Solar Cell Applications X
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Presentation Title |
Ultra-high Solubility of Al and Enhanced Thermopower in Fe2VAl1+x |
Author(s) |
Michael Parzer, Fabian Garmroudi, Alexander Riss, Takao Mori, Ernst Bauer |
On-Site Speaker (Planned) |
Michael Parzer |
Abstract Scope |
Recently, a record-breaking power factor of over 10 mW/mK2 was achieved in n-type Fe2VAl-based compounds, sparking new interest in full-Heusler systems for thermoelectrics. Here, we propose phase-boundary mapping in the Al-rich part of the phase diagram as a strategy to achieve high thermoelectric performance for p-type Fe2VAl-based compounds. Increasing the Al concentration up to Fe2VAl2, we find full solubility of Al using X-ray diffraction and scanning electron microscopy measurements. The transport properties - measured in a wide temperature range from 4-800 K - indicate non-rigid band structure behavior as the thermopower steadily increases up to Fe2VAl1.5, surpassing the original compound by over 100 %. Furthermore, the introduction of antisites into the crystal lattice leads to a significant reduction of the thermal conductivity. Therefore, this poses a powerful starting point for the discovery of new optimized thermoelectric materials, drastically extending the phase space of Fe-V-Al-based semiconducting compounds. |
Proceedings Inclusion? |
Planned: |
Keywords |
Electronic Materials, Energy Conversion and Storage, Characterization |