Li Chengjun, Li Wang, Sun Chengwei, Ma Zheng, Wei Yingchao, Ma Wenyuan, Yang Boyu, Li Xin, Luo Yubo, Yang Junyou
Sate Key Laboratory of Materials Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
ACS Appl Mater Interfaces. 2024 Aug 28;16(34):45224-45233. doi: 10.1021/acsami.4c11129. Epub 2024 Aug 16.
BiTe-based thin films are gaining recognition for their remarkable room temperature thermoelectric performance. Beyond the conventional "process-composition-performance" paradigm, it is highly desirable to explore new methods to enhance their performance further. Here, we designed a sandwich-structured Ag/PZT/PVDF/BiSbTe(BST) thin film device and effectively regulated the performance of the BST film by controlling the polarization state of the PZT/PVDF layers. Results indicate that polarization induces interlayer charge redistribution and charge transfer between PZT/PVDF and BST, thereby achieving the continuous modulation of the electrical transport characteristics of BST films. Finally, following polarization at a saturation voltage of 3 kV, the power factor of the BST film increased by 13% compared to the unpolarized condition, reaching 20.8 μW cm K. Furthermore, a device with 7 pairs of P-N legs was fabricated, achieving a cooling temperature difference of 11.0 K and a net cooling temperature difference of 2.4 K at a current of 10 mA after the saturation polarization of the PZT/PVDF layer. This work reveals the critical effect of introducing ferroelectric layer polarization to achieve excellent thermoelectric performance of the BST film.
基于BiTe的薄膜因其卓越的室温热电性能而受到认可。超越传统的“工艺-成分-性能”范式，迫切需要探索进一步提高其性能的新方法。在此，我们设计了一种三明治结构的Ag/PZT/PVDF/BiSbTe（BST）薄膜器件，并通过控制PZT/PVDF层的极化状态有效地调节了BST薄膜的性能。结果表明，极化诱导了层间电荷重新分布以及PZT/PVDF与BST之间的电荷转移，从而实现了对BST薄膜电输运特性的连续调制。最后，在3 kV饱和电压下极化后，BST薄膜的功率因子比未极化状态提高了13%，达到20.8 μW cm K。此外，制备了具有7对P-N腿的器件，在PZT/PVDF层饱和极化后，在10 mA电流下实现了11.0 K的冷却温差和2.4 K的净冷却温差。这项工作揭示了引入铁电层极化对实现BST薄膜优异热电性能的关键作用。
