Thermoelectric and thermophysical properties of ErPdX (X=Sb and Bi) half-Heusler compounds
Thermoelectric and thermophysical properties of ErPdX (X=Sb and Bi) half-Heusler compounds
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DOI：
10.1063/1.2196109
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发表时间：
2006-05
影响因子：
3.2
通讯作者：
T. Sekimoto;K. Kurosaki;H. Muta;S. Yamanaka
中科院分区：
文献类型：
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作者：
T. Sekimoto;K. Kurosaki;H. Muta;S. Yamanaka
采用放电等离子烧结技术制备了半Heusler化合物ErPdX(X=Sb和Bi)。测试了它们的高温热电性能和室温热物理性能。ErPdSb的电阻率ρ和热电势S都大于ErPdBi，两种化合物在高温下都表现出类似半导体的特征。ErPdSb在室温以上具有较大的功率因数(=S2/ρ)和10μW/K2 cm。由lnρ-1/T图估算出ErPdSb和ErPdBi的带隙能Eg分别为0.28 eV和0.05 eV。S-T和S-ln的ρ图表明，载流子的高温导电机制是本征导电。ρ和S在两种化合物中的差异是由载流子浓度的差异引起的，其大小源于Eg的差异和对化学计量组成的偏离。ErPdBi的总导热系数κ超过ErPdSb，这是因为ErPdSb的热导率较大。
Half-Heusler compounds ErPdX (X=Sb and Bi) were prepared by a spark plasma sintering technique. Their thermoelectric properties at high temperature and thermophysical properties at room temperature were measured. The electrical resistivity ρ and thermoelectric power S of ErPdSb are larger than those of ErPdBi, and both compounds indicate semiconductorlike characteristics at high temperature. ErPdSb has the large power factor (=S2∕ρ)>10μW∕K2cm above room temperature. From the lnρ-1∕T plot, the band gap energies Eg were estimated to be 0.28 and 0.05eV for ErPdSb and ErPdBi, respectively. The S-T and S-lnρ plots indicate that the conduction mechanism of the carriers is an intrinsic conduction at high temperature. The differences of ρ and S between both compounds are caused by the difference of the carrier concentration, whose magnitude originated in the difference of Eg and the deviation from the stoichiometric composition. The total thermal conductivity κ of ErPdBi exceeds that of ErPdSb because of the larg...