Nanoscale Thermoelectrics: A Study of the Absolute Seebeck Coefficient of Thin Films
Nanoscale Thermoelectrics: A Study of the Absolute Seebeck Coefficient of Thin Films
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纳米级热电学：薄膜绝对塞贝克系数的研究
DOI：
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发表时间：
2014
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影响因子：
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通讯作者：
Sarah C. Mason
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文献类型：
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作者：
Sarah C. Mason
世界对能源的需求不断增加。同样，由于通过燃烧化石燃料产生能源，气候变化对环境的影响越来越令人担忧。由于这些因素，人们不断地寻找新的可再生能源。热电装置能够从废热中产生清洁的、可再生的能量。无论多么有希望，它们的低效率严重限制了适用性和实际使用。热电材料的有用性随着无量纲量ZT而增加，其中Z = S2σ/κ，并且S、σ和κ分别是塞贝克系数以及电导率和热导率。这些特征材料参数具有相互依赖的能量传输贡献，其典型地禁止一个的优化而不损害另一个。在过去的十年中，由于热传导和电传导的解耦，ZT已经发生了令人鼓舞的进步。为了生产适用的设备，需要进一步的进步。解耦或调整能量传输特性的一个好方法是通过将尺寸减小到纳米级。然而，随着尺寸的减小，测量材料特性变得复杂。诸如塞贝克系数S之类的性质的测量主要取决于测量设备。塞贝克系数被定义为由热梯度产生的电压量。通过传统方法测量热产生的电压，得到V =（Ssample − Slead）Δ T。如果Slead的精确值可用，则简单的减法提供答案。这在纳米级测量中是很少发生的
The worlds demand for energy is ever increasing. Likewise, the environmental impact of climate change due generating that energy through combustion of fossil fuels is increasingly alarming. Due to these factors new sources of renewable energies are constantly being sought out. Thermoelectric devices have the ability to generate clean, renewable, energy out of waste heat. However promising that is, their inefficiency severely inhibits applicability and practical use. The usefulness of a thermoelectric material increases with the dimensionless quantity, ZT , where, Z = S2σ/κ, and S, σ, and κ are the Seebeck coefficient and electrical and thermal conductivities respectively. These characteristic material parameters have interdependent energy transport contributions that classically prohibit the optimization of one with out the detriment of another. Encouraging advancements of ZT have occurred in the past ten years due to the decoupling of the thermal and electrical conductivity. Further advancements are necessary in order to produce applicable devices. One auspicious way of decoupling or tuning energy transport properties, is through size reduction to the nanoscale. However, with reduced dimensions come complications in measuring material properties. Measurements of properties such as the Seebeck coefficient, S, are primarily contingent upon the measurement apparatus. The Seebeck coefficient is defined as the amount of voltage generated by a thermal gradient. Measuring a thermally generated voltage by traditional methods gives, V = (Ssample − Slead)∆T . If accurate values of, Slead, are available, simple subtraction provides the answer. This is rarely the case in nanoscale measurement