Effects of chemical potential on the thermoelectric performance of alkaline-earth based skutterudites (AFe4Sb12, A Ca, Sr and Ba)
| Autor: | M. Yazdani-Kachoei, Imad Khan, H. A. Rahnamaye Aliabad, Iftikhar Ahmad, S. Jalali-Asadabadi, Banaras Khan |
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| Rok vydání: | 2017 |
| Předmět: |
Alkaline earth metal
Materials science Valence (chemistry) Condensed matter physics Mechanical Engineering Metals and Alloys 02 engineering and technology Electronic structure 021001 nanoscience & nanotechnology Thermoelectric materials 01 natural sciences Mechanics of Materials 0103 physical sciences Thermoelectric effect Materials Chemistry Valence band Density of states 010306 general physics 0210 nano-technology Electronic density |
| Zdroj: | Journal of Alloys and Compounds. 694:253-260 |
| ISSN: | 0925-8388 |
| Popis: | In this paper we explore the electronic nature and thermoelectric properties of filled skutterudites AFe 4 Sb 12 (A Ca, Sr and Ba) by DFT and post-DFT techniques. The calculated results show that the filling of Ca, Sr, and Ba at the empty crystal sites enhances the thermoelectric performance of the host material. This increase is a consequence of the coupling between the guest and the host atoms, which affects the electronic density at different symmetry points that increases the density of states of the valence bands. The valence band edge is almost independent of the guest atoms, i.e., the s-bands of Ca, Sr and Ba have negligibly small contribution to the valence band edge. In these compounds, the maximum value of thermoelectric PF/τ of 42.43 × 10 14 μW/cmK 2 s and 33.57 × 10 14 μW/cmK 2 s for the n-type of SrFe 4 Sb 12 in the spin-up and down states respectively. The striking feature of these compounds is their effectiveness at the low chemical potential values for the best thermoelectric performance. |
| Databáze: | OpenAIRE |
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