ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Study of anisotropic thermal conductivity in textured thermoelectric alloys by Raman spectroscopy

Bose, RSC and Ramesh, K (2021) Study of anisotropic thermal conductivity in textured thermoelectric alloys by Raman spectroscopy. In: RSC Advances, 11 (39). pp. 24456-24465.

[img]
Preview
PDF
rsc_adv_11-39_24456-24465_2021.pdf - Published Version

Download (1MB) | Preview
[img]
Preview
PDF
d1ra04886d1.pdf - Published Supplemental Material

Download (1MB) | Preview
Official URL: https://doi.org/10.1039/d1ra04886d

Abstract

Polycrystalline p-type Sb1.5Bi0.5Te3(SBT) and n-type Bi2Te2.7Se0.3(BTS) compounds possessing layered crystal structure show anisotropic electronic and thermal transport properties. This research is in pursuit of better understanding the anisotropic thermal properties using Raman spectroscopy. A systematic Raman spectroscopic study of the hot-pressed pellet of the textured p-type SBT and n-type BTS is reported in both directions: parallel (�) and perpendicular (�) to the pressing axis as a function of temperature and laser power. The first-order temperature coefficient, optical thermal conductivity, and phonon lifetime are qualitatively determined from the temperature and laser power-dependent frequency and full-width half maximum (FWHM) of Raman peaks (A11g, E2g& A21g). Anisotropy in experimental phonon thermal conductivity in both directions is correlated with the approximated optical thermal conductivity, phonon lifetime and phonon anharmonicity. The anisotropy in phonon anharmonicity in both directions is explained by the modified Klemens-Hart-Aggarwal-Lax phonon decay model. In this study, the symmetric three-phonon scattering process is considered responsible for thermal transport in the temperature range of 300 to 473 K. © The Royal Society of Chemistry 2021.

Item Type: Journal Article
Publication: RSC Advances
Publisher: Royal Society of Chemistry
Additional Information: The copyright for this article belongs to Authors
Keywords: Anisotropy; Crystal structure; Phonons; Raman spectroscopy; Spectroscopic analysis; Temperature; Textures, Dependent frequencies; Electronic and thermal transports; Full width half maximum; Layered crystal structure; Phonon thermal conductivity; Raman spectroscopic study; Thermoelectric alloys; Three-phonon scattering, Thermal conductivity of solids
Department/Centre: Division of Physical & Mathematical Sciences > Physics
Date Deposited: 20 Nov 2021 11:32
Last Modified: 20 Nov 2021 11:32
URI: http://eprints.iisc.ac.in/id/eprint/69866

Actions (login required)

View Item View Item