Ruiz-Clavijo Alejandra, Caballero-Calero Olga, Manzano Cristina V, Maeder Xavier, Beardo Albert, Cartoixà Xavier, Álvarez F Xavier, Martín-González Marisol
Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC) Isaac Newton, 8, E-28760 Tres Cantos, Madrid, Spain.
EMPA, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland.
ACS Appl Energy Mater. 2021 Dec 27;4(12):13556-13566. doi: 10.1021/acsaem.1c02129. Epub 2021 Dec 13.
3D interconnected nanowire scaffoldings are shown to increase the thermoelectric efficiency in comparison to similar diameter 1D nanowires and films grown under similar electrodeposition conditions. BiTe 3D nanonetworks offer a reduction in thermal conductivity (κ) while preserving the high electrical conductivity of the films. The reduction in κ is modeled using the hydrodynamic heat transport equation, and it can be understood as a heat viscosity effect due to the 3D nanostructuration. In addition, the Seebeck coefficient is twice that of nanowires and films, and up to 50% higher than in a single crystal. This increase is interpreted as a nonequilibrium effect that the geometry of the structure induces on the distribution function of the phonons, producing an enhanced phonon drag. These thermoelectric metamaterials have higher performance and are fabricated with large areas by a cost-effective method, which makes them suitable for up-scale production.
与在类似电沉积条件下生长的直径相似的一维纳米线和薄膜相比，三维互连纳米线支架显示出能提高热电效率。BiTe三维纳米网络在保持薄膜高电导率的同时，降低了热导率（κ）。κ的降低是使用流体动力学热传输方程进行建模的，并且可以理解为由于三维纳米结构而产生的热粘性效应。此外，塞贝克系数是纳米线和薄膜的两倍，比单晶高出50%。这种增加被解释为结构几何形状对声子分布函数产生的非平衡效应，从而产生增强的声子拖拽。这些热电超材料具有更高的性能，并且通过一种经济高效的方法大面积制造，这使其适合大规模生产。
