Thermal conductivity of porous polycrystalline PbTe
Thermal conductivity of porous polycrystalline PbTe
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DOI：
10.1103/physrevmaterials.5.014604
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发表时间：
2020-04
期刊：
影响因子：
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通讯作者：
Javier F. Troncoso;P. Chudzinski;T. Todorov;P. Aguado-Puente;M. Grüning;J. Kohanoff
中科院分区：
文献类型：
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作者：
Javier F. Troncoso;P. Chudzinski;T. Todorov;P. Aguado-Puente;M. Grüning;J. Kohanoff
热电材料的效率是通过降低其导热系数来提高的。在中等温度下，PbTe是最有前途的材料之一。晶界可以通过散射和限制声子来降低其固有的低导热系数。利用分子动力学参数化的相场模型，我们发现在多孔材料中，低温下PbTe的导热系数降低了35%。我们观察到，在有限密度的空洞中，相变控制着齐纳钉钉阻碍晶粒生长的动力学。
The efficiency of thermoelectric materials is enhanced by lowering their thermal conductivity. At intermediate temperatures, PbTe is one of the most promising materials. Grain boundaries can lower its inherently low thermal conductivity by scattering and confining phonons. Using a phase-field model parametrized by molecular dynamics, we find that in the porous material the thermal conductivity of PbTe is reduced by up to 35 % at low temperatures. We observe that a phase transition at a finite density of voids governs the kinetics of impeding grain growth by Zener pinning.