Comparative Study of Thermoelectric Properties of Sb2Si2Te6and Bi2Si2Te6

Autor: Jang, Hanhwi, Abbey, Stanley, Frimpong, Brakowaa, Nguyen, Chien Viet, Ziolkowski, Pawel, Oppitz, Gregor, Kim, Moohyun, Song, Jae Yong, Shin, Ho Sun, Jung, Yeon Sik, Oh, Min-Wook
Zdroj: ACS Applied Materials & Interfaces; 20220101, Issue: Preprints
Abstrakt: Charge carrier transport and corresponding thermoelectric properties are often affected by several parameters, necessitating a thorough comparative study for a profound understanding of the detailed conduction mechanism. Here, as a model system, we compare the electronic transport properties of two layered semiconductors, Sb2Si2Te6and Bi2Si2Te6. Both materials have similar grain sizes and morphologies, yet their conduction characteristics are significantly different. We found that phase boundary scattering can be one of the main factors for Bi2Si2Te6to experience significant charge carrier scattering, whereas Sb2Si2Te6is relatively unaffected by the phenomenon. Furthermore, extensive point defect scattering in Sb2Si2Te6significantly reduces its lattice thermal conductivity and results in high zTvalues across a broad temperature range. These findings provide novel insights into electron transport within these materials and should lead to strategies for further improving their thermoelectric performance.
Databáze: Supplemental Index