Zhang Yanjun, Zhao Yaxin, Guo Rui, Zhang Zengxing, Liu Dan, Xue Chenyang
State Key Laboratory of Dynamic Measurement Technology, School of Instrument and Electronics, North University of China, Taiyuan 030051, China.
Nanomaterials (Basel). 2022 Feb 12;12(4):624. doi: 10.3390/nano12040624.
Currently, there are several thermoelectric materials, such as AgTe, BiTe, and SbTe, that have been investigated for thermoelectric applications. However, the toxicity and rarity of most of these materials make them unsuitable for practical applications. In contrast, silver selenide (AgSe) is an abundant and environment-friendly thermoelectric material. This study provides a facile synthetic approach for preparing high-performance, low-cost, and flexible AgSe thermoelectric films. AgSe nanomaterials were prepared based on the chemical template method, and the reaction solution concentration was varied to systematically investigate the effects of reaction solution concentration on the characterization and thermoelectric properties of AgSe nanomaterials. For convenience of testing, the flexible AgSe films were prepared on porous nylon membranes using vacuum-assisted filtration. The prepared thermoelectric films were tested using an X-ray diffractometer, scanning electron microscope, Seebeck coefficient tester, and Hall tester. The film prepared from the solution with the lowest concentration (18.0 mM) demonstrated the best thermoelectric performance, with a maximum power factor of 382.18 μW∙m∙K at ~400 K. Additionally, a cold-pressing treatment could effectively enhance the electrical conductivity of the film, without damaging the substrate, as the conductivity of the film remained at 90% of the original value after 1500 bending cycles.
目前，有几种热电材料，如AgTe、BiTe和SbTe，已被研究用于热电应用。然而，这些材料中的大多数具有毒性且稀有，这使得它们不适合实际应用。相比之下，硒化银（AgSe）是一种储量丰富且环境友好的热电材料。本研究提供了一种简便的合成方法来制备高性能、低成本且柔性的AgSe热电薄膜。基于化学模板法制备了AgSe纳米材料，并改变反应溶液浓度以系统研究反应溶液浓度对AgSe纳米材料的表征和热电性能的影响。为便于测试，使用真空辅助过滤在多孔尼龙膜上制备了柔性AgSe薄膜。使用X射线衍射仪、扫描电子显微镜、塞贝克系数测试仪和霍尔测试仪对制备的热电薄膜进行了测试。由最低浓度（18.0 mM）的溶液制备的薄膜表现出最佳的热电性能，在约400 K时最大功率因数为382.18 μW∙m∙K。此外，冷压处理可以有效提高薄膜的电导率，且不会损坏基底，因为在1500次弯曲循环后薄膜的电导率仍保持在原始值的90%。
