Thermoelectric properties of Heusler-type compound Fe2V1−xNbxAl
Thermoelectric properties of Heusler-type compound Fe2V1−xNbxAl
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DOI：
10.1063/1.3609075
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发表时间：
2011-07
影响因子：
3.2
通讯作者：
Bin Xu;Yuanxu Wang;Wen-jie Zhao;Yuli Yan
中科院分区：
文献类型：
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作者：
Bin Xu;Yuanxu Wang;Wen-jie Zhao;Yuli Yan
用全势线性化缀加平面波方法和半经典玻尔兹曼理论计算了Fe2V1−xNbxAl的输运性质。所得塞贝克系数与实验结果吻合较好。化学计量比Fe2VAl的主要载体是空穴。当V被Nb轻微取代时，Seebeck系数迅速变为负值，导致主要载流子由空穴转变为电子。化学计量比Fe_2VAl的σ/τ表现出半导体行为。化学计量比的Fe_2VAl的功率因数S_2·σ/τ相对较小，在360K以下时，功率因数大大增加。由于塞贝克系数的提高，−_xNb_xAl(x≠_0)的低温功率因数显著增加。
The transport properties are calculated within the full-potential linearized augmented plane-wave method and the semi-classical Boltzmann theory on the Heusler-type compound Fe2V1−xNbxAl. The obtained Seebeck coefficients are in reasonable agreement with experimental results. The majority carriers of stoichiometric Fe2VAl are holes. When V is slightly replaced by Nb, the Seebeck coefficient becomes negative rapidly resulting in the main carrier changing from hole to electron. σ/τ of stoichiometric Fe2VAl exhibits semiconductor behavior. However, it transits into semimetal when V is replaced by Nb at low temperature and all Nb-substituted samples exhibit semiconducting behavior above 100 K. The power factor S2σ/τ of stoichiometric Fe2VAl is relative small, and it increases greatly after Nb substitution below 360 K. The low temperature power factor of Fe2V1−xNbxAl (x ≠ 0) increases dramatically due to the enhanced Seebeck coefficient.