Atomistic design of thermoelectric properties of silicon nanowires.
Atomistic design of thermoelectric properties of silicon nanowires.
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DOI：
10.1021/nl073231d
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发表时间：
2008-02
期刊：
影响因子：
10.8
通讯作者：
T. Vo;A. Williamson;V. Lordi;G. Galli
中科院分区：
文献类型：
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作者：
T. Vo;A. Williamson;V. Lordi;G. Galli
我们提出的预测的热电优值（ZT）的硅纳米线的直径可达3 nm，玻尔兹曼输运方程和从头计算的电子结构计算的基础上。我们发现，ZT显着依赖于线的生长方向和表面重建，我们讨论了如何调整这些属性可以选择硅基纳米结构与组合的n型和p型最佳ZT。我们的计算表明，只有通过减少约2或3个数量级的离子热导率相对于体积值，可以达到ZT大于1，分别为1或3纳米的线。我们还发现，ZT的p型掺杂的导线是相当小的比它们的n型掺杂的对应物具有相同的尺寸和几何形状。
We present predictions of the thermoelectric figure of merit ( ZT) of Si nanowires with diameter up to 3 nm, based upon the Boltzman transport equation and ab initio electronic structure calculations. We find that ZT depends significantly on the wire growth direction and surface reconstruction, and we discuss how these properties can be tuned to select silicon based nanostructures with combined n-type and p-type optimal ZT. Our calculations show that only by reducing the ionic thermal conductivity by about 2 or 3 orders of magnitudes with respect to bulk values, one may attain ZT larger than 1, for 1 or 3 nm wires, respectively. We also find that ZT of p-doped wires is considerably smaller than that of their n-doped counterparts with the same size and geometry.