Download all files (9.43 MB)

Collection

Citation

Description:

Bismuth telluride (Bi2Te3) and its alloys are among the best thermoelectric materials at room temperature. Bi14Te13S8, a material with a similar crystal structure, contains sulphur that can potentially improve thermoelectric performance through widening bandgap and reduced lattice thermal conductivity. This compound forms in sulphur added Bi2Te3 alloys. Here, polycrystalline iodine-doped Bi14Te13S8 sample is investigated; an optimum iodine concentration of 1 at% resulted in the power factor of 3.5 mWm−2 K−1 at room temperature. Iodine doping reduced the lattice thermal conductivity for more than 30% by enhancing phonon scattering. An improved thermoelectric figure of merit zT of ∼0.29 at 520 K was obtained for 1-1.5 at% iodine doped Bi14Te13S8. First-principles calculations indicate that Bi14Te13S8 has a larger band gap compared to bismuth telluride, which allows for a reduction in the bipolar effect, however, a lower effective mass reduced the thermopower for a similar carrier concentration. This study demonstrates that tuned iodine doping can effectively optimise the thermoelectric performance of Bi14Te13S8, highlighting its contribution in multiphase sulphur alloyed Bi2Te3-based materials.

Rights:

• In Copyright
  

  This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Applied Electronic Materials, copyright © 2024 American Chemical Society after peer review. To access the final edited and published work see https://doi.org/10.1021/acsaelm.3c01615

Keyword: thermoelectric

Date published: 2024-02-27

Publisher: American Chemical Society (ACS)

Journal:

• ACS Applied Electronic Materials (ISSN: 26376113) vol. 6 issue. 2 p. 1283-1291

Funding:

• H2020 Marie Sklodowska-Curie Actions Grant Agreement No. 801604
• JST Mirai Program Grant Number JPMJMI19A1
• JST SPRING Grant Number JPMJSP2124

Manuscript type: Author's version (Submitted manuscript)

MDR DOI: https://doi.org/10.48505/nims.4608

First published URL: https://doi.org/10.1021/acsaelm.3c01615

Related item:

Other identifier(s):

Contact agent:

Updated at: 2024-07-29 16:30:15 +0900

Published on MDR: 2024-07-29 16:30:15 +0900