Tuning Thermoelectric Conversion Performance of BiSbTe/Epoxy Flexible Films with Dot Magnetic Arrays

ACS Appl Mater Interfaces. 2023 Feb 8;15(5):7112-7119. doi: 10.1021/acsami.2c20348. Epub 2023 Jan 30.

Abstract

Embedding of magnetic functional units into the thermoelectric (TE) materials has been demonstrated to be an effective way to enhance the TE conversion performance. However, the magnetic functional units in TE materials are all randomly distributed. In this paper, to explore the effect of the ordering of the magnetic functional units on TE conversion performance, a series of BiSbTe/epoxy flexible thermoelectromagnetic (TEM) films with dot magnetic arrays were successfully prepared by a two-step screen printing combined with a hot pressing process. TEM films with dot magnetic arrays can achieve high carrier mobility, while the carrier concentration increases due to large coercivity. Therefore, its electrical conductivities are significantly improved on the condition that it maintains a high Seebeck coefficient. The TEM film with hexagonal-dot magnetic arrays exhibits the best electrical transport properties, for which the room-temperature power factor reaches 1.51 mW·m-1·K-2, increased by 33.6 and 36.1% as compared with those of the pristine TE film and the TEM film with a continuous magnetic layer, respectively. This work provides a new way to enhance the TE conversion performance of flexible TEM films through the ordered magnetic arrays.

Keywords: TE conversion performance; TEM films; cooling performance; dot magnetic arrays; electrical transport properties.