Pan Yu, He Bin, Helm Toni, Chen Dong, Schnelle Walter, Felser Claudia
Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, Dresden, 01187, Germany.
Dresden High Magnetic Field Laboratory (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf, Dresden, 01328, Germany.
Nat Commun. 2022 Jul 7;13(1):3909. doi: 10.1038/s41467-022-31372-7.
Topological semimetals are well known for their interesting physical properties, while their mechanical properties have rarely received attention. With the increasing demand for flexible electronics, we explore the great potential of the van der Waals bonded Weyl semimetal WTe for flexible thermoelectric applications. We find that WTe single crystals have an ultrahigh Nernst power factor of ~3 WmK, which outperforms the conventional Seebeck power factors of the state-of-the-art thermoelectric semiconductors by 2-3 orders of magnitude. A unique band structure that hosts compensated electrons and holes with extremely high mobilities is the primary mechanism for this huge Nernst power factor. Moreover, a large Ettingshausen signal of ~5 × 10 KAm is observed at 23.1 K and 9 T. In this work, the combination of the exceptional Nernst-Ettingshausen performance and excellent mechanical transformative ability of WTe would be instructive for flexible micro-/nano-thermoelectric devices.
拓扑半金属因其有趣的物理性质而闻名，但其机械性能很少受到关注。随着对柔性电子器件需求的增加，我们探索了范德华键合的外尔半金属WTe在柔性热电应用中的巨大潜力。我们发现WTe单晶具有约3 WmK的超高能斯特功率因数，比最先进的热电半导体的传统塞贝克功率因数高出2至3个数量级。具有补偿电子和空穴且迁移率极高的独特能带结构是这种巨大能斯特功率因数的主要机制。此外，在23.1 K和9 T时观察到约5×10 KAm的大能廷斯豪森信号。在这项工作中，WTe卓越的能斯特-廷斯豪森性能与出色的机械变形能力相结合，将对柔性微/纳热电器件具有指导意义。
