Tunable Low-Temperature Thermoelectric Transport Properties in Layered CuCr(S1-xSex)2 System
Loading...
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Date
2023-07-17
Major/Subject
Mcode
Degree programme
Language
en
Pages
Series
Zeitschrift fur Anorganische und Allgemeine Chemie, Volume 649, issue 14
Abstract
We have characterized the layered CuCr(S,Se)2 system for the spin-polarized electronic band structures and low-temperature thermoelectric transport properties. The electronic band structure calculations reveal semiconducting behavior for CuCrS2, CuCr(S0.5Se0.5)2 and CuCrSe2 with an indirect bandgap of 0.42, 0.30 and 0.10 eV, respectively. The systematically decreased bandgap with increasing Se content is in line with the experimental observations showing a semiconductor-to-metal transition with increasing Se-substitution level in the CuCr(S1-xSex)2 system because of an increase in the charge carrier density. The p-type Seebeck coefficient shows a linear temperature dependence for the samples, like in degenerate semiconductors or metals. The remarkably large Seebeck coefficient even in metallic samples is due to a relatively large effective mass of charge carriers. As the thermal conductivity is intrinsically low owing to the layered crystal structure and is further decreased for the Se-substituted samples because of the increased phonon scattering from point defects, the thermoelectric characteristics are promising. The highest dimensionless figure-of-merit values were seen for the x=0.5 sample, e. g., 0.04 at 400 K.Description
Funding Information: HSK would like to acknowledge Jenny Ja Antti Wihuri foundation for research grant (2021‐2023). The authors would also like to acknowledge Academy of Finland (Profi3 and PREIN). This work made use of the RawMatters Finland infrastructure (RAMI) facilities at Aalto University. Publisher Copyright: © 2023 The Authors. Zeitschrift für anorganische und allgemeine Chemie published by Wiley-VCH GmbH.
Keywords
Other note
Citation
Kousar, H S, Srivastava, D, Karppinen, M & Tewari, G C 2023, ' Tunable Low-Temperature Thermoelectric Transport Properties in Layered CuCr(S 1-x Se x ) 2 System ', Zeitschrift fur Anorganische und Allgemeine Chemie, vol. 649, no. 14, e202300079 . https://doi.org/10.1002/zaac.202300079