Low-cost material conducts electricity with higher stability, 100% efficiency increase

Yahoo

06-05-2025

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Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience.
Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Generate Key Takeaways
A team scientists have succeeded in producing new and efficient thermoelectric materials that could compete with state-of-the-art materials, offering greater stability and lower cost.
Thermoelectric materials enable the direct conversion of heat into electrical energy. The latest innovation offers new properties through a new combination of materials.
Researchers have highlighted that good thermoelectric materials are those that conduct electricity well on the one hand, but transport heat as poorly as possible on the other – an apparent contradiction, as good electrical conductors are generally also good conductors of heat.
Scientists try to suppress heat transport through lattice vibrations
"In solid matter, heat is transferred both by mobile charge carriers and by vibrations of the atoms in the crystal lattice. In thermoelectric materials, we mainly try to suppress heat transport through the lattice vibrations, as they do not contribute to energy conversion," said first author Fabian Garmroudi, who obtained his doctorate at TU Wien.
This makes them particularly attractive for the emerging for the autonomous energy supply of microsensors and other tiny electronic components.
In order to make the materials more efficient, at the same time heat transport via the lattice vibrations must be suppressed and the mobility of the electrons increased – a hurdle that has often hindered research until now.
Powder of an alloy of iron, vanadium, tantalum and aluminum used
Published in the journal Nature Communications, the study demonstrates that by incorporating chemically and structurally distinct archetypal topological insulator Bi1−xSbx at the grain boundaries, charge, and heat transport can be decoupled, "resulting in a reduction of κL, and simultaneously, in an unexpected increase of μW."
'Supported by the Lions Award, I was able to develop new hybrid materials at the National Institute for Materials Science in Japan that exhibit exceptional thermoelectric properties,' recalls Garmroudi of his research stay in Tsukuba (Japan), which he completed as part of his work at TU Wien.
Specifically, powder of an alloy of iron, vanadium, tantalum and aluminum (Fe2V0.95Ta0.1Al0.95) was mixed with a powder of bismuth and antimony (Bi0.9Sb0.1) and pressed into a compact material under high pressure and temperature. Due to their different chemical and mechanical properties, however, the two components do not mix at an atomic level. Instead, the BiSb material is preferentially deposited at the micrometer-sized interfaces between the crystals of the FeVTaAl alloy, according to a press release.
Researchers highlighted that the lattice structures of the two materials, and therefore also their quantum mechanically permitted lattice vibrations, are so different that thermal vibrations cannot simply be transferred from one crystal to the other.
Researchers added that the targeted decoupling of heat and charge transport enabled the team to increase the efficiency of the material by more than 100 %.
"This brings us a big step closer to our goal of developing a thermoelectric material that can compete with commercially available compounds based on bismuth telluride," said Garmroudi.