Effect of Silicon Substitution on Thermoelectric Properties of Heusler-type Fe 2 VAl Alloy
Effect of Silicon Substitution on Thermoelectric Properties of Heusler-type Fe 2 VAl Alloy
复制标题
硅取代对Heusler型Fe 2 VAl合金热电性能的影响
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
S. Asano
中科院分区：
文献类型：
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作者：
H. Kato;Masaaki Kato;Y. Nishino;U. Mizutani;S. Asano
本文报道了Si成分y=0 <$0.20的Fe_2 VAl_（1-y）Si_y合金的电阻率、Seebeck系数和Hall系数随温度的变化关系。虽然Heusler型Fe_2VAl（y=0）表现出类似半导体的电阻率行为，但Si对Al的轻微取代导致低温电阻率急剧下降和Seebeck系数的大幅增强。塞贝克系数的大幅增强与霍尔系数的变化是合理的雅阁，并且可以在电子结构的基础上进行解释，其中费米能级从赝能隙的中心略微偏移，这是由于Si的取代。特别地，y=0.10的Si替代导致室温下5.4×10-3 W/mK2的大功率因数，这与常规热电材料相当。
We report on the temperature dependence of electrical resistivity, Seebeck coefficient and Hall coefficient of the Fe2VAl1-ySiy alloys with Si compositions y=00.20. While the Heuslertype Fe2VAl ( y=0) exhibits a semiconductorlike resistivity behavior, a slight substitution of Si for Al causes a sharp decrease in the low temperature resistivity and a large enhancement in the Seebeck coefficient. Substantial enhancements for the Seebeck coefficient are in reasonable accord with changes in the Hall coefficient and can be explained on the basis of the electronic structure, where the Fermi level shifts slightly from the center of the pseudogap due to the substitution of Si. In particular, the Si substitution of y=0.10 leads to a large power factor of 5.4×10-3 W/m K2 at room temperature, which is comparable to that of conventional thermoelectric materials.