| Autor: |
Hezhang Li, Kei Hayashi, Jinfeng Dong, Jing-Feng Li, Yuzuru Miyazaki |
| Jazyk: |
angličtina |
| Rok vydání: |
2020 |
| Předmět: |
|
| Zdroj: |
Materials Research Express, Vol 7, Iss 5, p 055503 (2020) |
| Druh dokumentu: |
article |
| ISSN: |
2053-1591 |
| DOI: |
10.1088/2053-1591/ab875b |
| Popis: |
Full-Heusler compounds have three crystal structures with a different order degree; the highly ordered L2 _1 , partially disordered B2, and completely disordered A2 structures. To reveal the effects of the order degree on thermoelectric (TE) properties of the full-Heusler compounds, Mn _2 VAl samples with varied L2 _1 and B2 order degrees are prepared by changing preparation conditions, and their Seebeck coefficients and electrical conductivities are measured in a wide temperature range. As the B2 order degree becomes higher, the Seebeck coefficient increases, leading to the increase of the power factor (PF). The maximum PF is 2.84 × 10 ^−4 Wm ^−1 K ^−2 at 767 K for the Mn _2 VAl sample with the highest B2 order degree. This study demonstrates that the TE properties of Mn _2 VAl can be enhanced by increasing the fraction of the B2 phase. A relation between the Seebeck coefficient and crystal structures is also discussed based on the calculation of the electronic density of states of Mn _2 VAl with the L2 _1 and B2 structures. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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