| Autor: |
Hezhang Li, Kei Hayashi, Zhicheng Huang, Hiroto Takeuchi, Gakuto Kanno, Jing-Feng Li, Yuzuru Miyazaki |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Journal of Materiomics, Vol 10, Iss 2, Pp 511-519 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2352-8478 |
| DOI: |
10.1016/j.jmat.2023.11.013 |
| Popis: |
A half-metallic full-Heusler Mn2VAl alloy is a potential p-type thermoelectric material that can directly generate electricity from waste heat via the Seebeck effect. For practical use, the Seebeck coefficient S of Mn2VAl should be increased while maintaining a high electrical conductivity σ from its half-metallic character. Herein, we achieved this objective through antisite defect engineering. Theoretically, it was predicted that the S was maximized by regulating partial density of states of majority-spin sp-electrons through the control of the fraction of antisite defect, fAD, between V and Al atoms in Mn2VAl. Experimentally, a significant increase in S and a slight decrease in σ were observed for an Mn2VAl sample with an optimal fAD = 33%, enhancing the thermoelectric power factor PF by 2.7 times from an Mn2VAl sample with fAD = 14%. Furthermore, we combined the antisite defect engineering with a partial substitution method. An Mn2V(Al0.96Si0.04) sample with fAD = 33% exhibited the highest PF = 4.5 × 10−4 W·m−1·K−2 at 767 K among the samples. The maximum dimensionless figure-of-merit zT of the Mn2V(Al0.96Si0.04) sample with fAD = 33% was measured to be 3.4 × 10−2 at 767 K, which is the highest among the p-type half-metallic full-Heusler alloys. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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