Na Yin Hongchao Wang Chunlei Wang
材料科学技术（英文）
Lanthanum ferrites ceramics La0.9A0.1FeO3 (A=Mg, Ca, Sr, Ba) have been prepared by solid state reaction. X-ray power diffraction analysis reveals that all samples are of pure perovskite structure with orthorhombic phase. Electrical conductivity and Seebeck coefficient have been measured in vacuum within the temperature range between room temperature and 800°C. The electrical conductivity shows semiconducting behavior. Temperature dependence of electrical conductivity indicates that adiabatic small-polaron hopping mechanism is dominant for their electric transportations. Seebeck coefficients are positive for samples, suggesting p-type conduction in the whole temperature range. The highest Seebeck coefficient is found to be 654 μV/K for La0.9Mg0.1 FeO3. Except La0.9Ba0.1FeO3, the electrical conductivity of La0.9A 0.1FeO3 increases with increasing atomic number of the A-site element, while Seebeck coefficient decreases.
关键词:
La0:9A0:1FeO3 ceramics
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electrical conductivity
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Seebeck coefficient
赵杰
,
辛彩妮
,
韩叶茂
,
周敏
,
黄荣进
,
李来风
材料研究学报
用机械合金(MA)和放电等离子烧结(SPS)方法制备出Nb掺杂的Pb1.1Te合金块体,在323-673 K温区内测试其电阻率、Seebeck系数和热扩散系数,并计算其热电优值.结果表明:在PbHTe中掺杂Nb能有效提高材料的载流子浓度,优化其电性能,使Pb10Nb0.07Te的功率因子在523-673K温区范围内超过20 mW/(cm· K2).同时,Nb的引入可增强声子散射,降低晶格热导率,从而得到较高的热电优值.样品Pb103Nb007Te在673 K时ZT值最大为1.27,是基体材料Pb11Te的2倍.
关键词:
金属材料
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Seebeck系数
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晶格热导率
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n型PbTe合金
