Magnetic-Field Dependence of Thermoelectric Properties of Sintered Bi90Sb10 Alloy
Magnetic-Field Dependence of Thermoelectric Properties of Sintered Bi90Sb10 Alloy
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烧结 Bi90Sb10 合金热电性能的磁场依赖性
DOI：
10.1007/s11664-015-4270-y
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
and Takashi Komine
中科院分区：
文献类型：
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作者：
Masayuki Murata;Atsushi Yamamoto;Yasuhiro Hasegawa;and Takashi Komine
对烧结Bi 90 Sb 10合金的热电性能和无量纲优值（ZT）随磁场的变化进行了实验和理论研究。采用熔融法在石英安瓿中合成Bi-Sb合金，然后通过球磨研磨所得铸锭。采用放电等离子烧结（SPS）方法制备了粒度在几微米到几十微米范围内的烧结Bi 90 Sb 10合金。在77-300 K的温度下，对于高达2.9 T的磁场，实验评估了电阻率、塞贝克系数和热导率的磁场依赖性。结果表明，在2.5T的磁场作用下，在300 K时，ZT提高了37%。基于弛豫时间近似的玻尔兹曼方程的磁塞贝克系数的理论计算也进行了。从而定性和定量地解释了300 K下Bi 90 Sb 10合金的磁塞贝克系数的实验结果。具体地说，载流子散射机制被证明是声学声子势散射和载流子迁移率比之间的L-和T-点被发现是3.3，这对应于一个单晶的特性。结果表明，理论计算模型准确地反映了磁场对Seebeck系数的影响。
The magnetic-field dependence of the thermoelectric properties and dimensionless figure of merit (ZT) of a sintered Bi90Sb10alloy were experimentally and theoretically evaluated. The Bi-Sb alloy was synthesized in a quartz ampule using the melting method, and the resultant ingot was then ground via ball milling. A sintered Bi90Sb10alloy with a particle size in the range of several to several tens of micrometers was prepared using the spark plasma sintering (SPS) method. The magnetic-field dependence of the electrical resistivity, Seebeck coefficient, and thermal conductivity were experimentally evaluated at temperatures of 77–300 K for magnetic fields of up to 2.9 T. The results showed thatZTincreased by 37% at 300 K under a 2.5-T magnetic field. A theoretical calculation of the magneto-Seebeck coefficient based on the Boltzmann equation with a relaxation time approximation was also performed. Hence, the experimental result for the magneto-Seebeck coefficient of the Bi90Sb10alloy at 300 K was qualitatively and quantitatively explained. Specifically, the carrier scattering mechanism was shown to be acoustic phonon potential scattering and the carrier mobility ratio between theL- andT-points was found to be 3.3, which corresponds to the characteristics of a single crystal. It was concluded that the effect of the magnetic field on the Seebeck coefficient was demonstrated accurately using the theoretical calculation model.