In a complex nanostructured material or composite, the thermoelectric figure of merit, , is strongly dependent on the morphology and transport properties of interfacial areas that connect individual crystal grains or composite constituent phases. Despite the active efforts to improve , relatively few experimental and theoretical investigations have been focused on probing the interfacial transport properties of relevant materials. We developed a finite element method based mesoscale-level simulation approach to evaluate the effective values of thermal and electrical conductivities, and Seebeck coefficient in structurally complex materials. This approach was tested on three popular nanocrystalline thermoelectric systems: n-type Si, n-type SiGe, and p-type BiSbTe, providing excellent agreement between the simulated and previously measured values of . The interfacial thermoelectric properties of these material systems were quantified in the process and compared to simple models. Furthermore, the sensitivity of to changes in the system morphology was elucidated as well.

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预测复杂材料的热电品质因数：我们需要知道什么？

在复杂的纳米结构材料或复合材料中，热电品质因数强烈依赖于连接单个晶粒或复合材料组成相的界面区域的形态和传输特性。尽管人们积极努力改进，但相对较少的实验和理论研究集中在探讨相关材料的界面传输特性。我们开发了一种基于有限元方法的介观级模拟方法，用于评估结构复杂材料中热导率、电导率以及塞贝克系数的有效值。该方法在三种流行的纳米晶热电系统上进行了测试：n 型 Si、n 型 SiGe 和 p 型 BiSbTe，在 的模拟值和之前的测量值之间提供了极好的一致性。这些材料系统的界面热电特性在此过程中被量化，并与简单模型进行比较。此外，还阐明了对系统形态变化的敏感性。