The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K

The effects of high-pressure compression on the transport and thermoelectric properties of TiS2 were investigated at temperatures ranging from 5 to 310 K. The results indicated that compression under the pressure of 6 GPa caused a significant decrease (16-fold at 300 K) in the absolute thermopowe...

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Main Authors: Hng, Huey Hoon, Li, D., Qin, X. Y., Li, H. J., Zhang, J.
Other Authors: School of Materials Science & Engineering
Format: Article
Language:English
Published: 2014
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Online Access:https://hdl.handle.net/10356/101832
http://hdl.handle.net/10220/18825
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Institution: Nanyang Technological University
Language: English
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spelling sg-ntu-dr.10356-1018322023-07-14T15:57:35Z The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K Hng, Huey Hoon Li, D. Qin, X. Y. Li, H. J. Zhang, J. School of Materials Science & Engineering DRNTU::Science::Physics The effects of high-pressure compression on the transport and thermoelectric properties of TiS2 were investigated at temperatures ranging from 5 to 310 K. The results indicated that compression under the pressure of 6 GPa caused a significant decrease (16-fold at 300 K) in the absolute thermopower |S| and the thermal conductivity (5-fold at 300 K). At the same time, the electrical resistivity ρ increased by two orders of magnitude after the compression. A transition from metallic state (dρ /dT>0) to semiconductorlike state (dρ /dT<0) was found to occur after the compression. This transition to the semiconductorlike state could be caused by the substantially enhanced grain boundary (GB) scattering due to the refinement of its grains to the nanoscale range, which should also be responsible for the remarkable increase in the resistivity and large decrease in thermal conductivity. Moreover, Mott’s two-dimensional variable range hopping law, ln ρ∝T-1/3, was observed at T<~100 K for TiS2 after the compression, suggesting that substantial potential disorder was produced by the high-pressure compression. The significant decrease of |S| could originate from the possible compositional disorder in the GBs of TiS2 after compression. The thermoelectric figure of merit of TiS2 decreased after the compaction due to the large decrease in |S| and increase in ρ, indicating that high-pressure compression is not beneficial to the thermoelectric performance of TiS2. Published version 2014-02-18T05:48:59Z 2019-12-06T20:45:14Z 2014-02-18T05:48:59Z 2019-12-06T20:45:14Z 2008 2008 Journal Article Li, D., Qin, X. Y., Li, H. J., Zhang, J. & Hng, H. H. (2008). The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K. Journal of applied physics, 103(12), 123704-. https://hdl.handle.net/10356/101832 http://hdl.handle.net/10220/18825 10.1063/1.2938748 en Journal of applied physics © 2008 American Institute of Physics. This paper was published in Journal of Applied Physics and is made available as an electronic reprint (preprint) with permission of American Institute of Physics. The paper can be found at the following official URL: [http://dx.doi.org/10.1063/1.2938748]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law. application/pdf
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic DRNTU::Science::Physics
spellingShingle DRNTU::Science::Physics
Hng, Huey Hoon
Li, D.
Qin, X. Y.
Li, H. J.
Zhang, J.
The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
description The effects of high-pressure compression on the transport and thermoelectric properties of TiS2 were investigated at temperatures ranging from 5 to 310 K. The results indicated that compression under the pressure of 6 GPa caused a significant decrease (16-fold at 300 K) in the absolute thermopower |S| and the thermal conductivity (5-fold at 300 K). At the same time, the electrical resistivity ρ increased by two orders of magnitude after the compression. A transition from metallic state (dρ /dT>0) to semiconductorlike state (dρ /dT<0) was found to occur after the compression. This transition to the semiconductorlike state could be caused by the substantially enhanced grain boundary (GB) scattering due to the refinement of its grains to the nanoscale range, which should also be responsible for the remarkable increase in the resistivity and large decrease in thermal conductivity. Moreover, Mott’s two-dimensional variable range hopping law, ln ρ∝T-1/3, was observed at T<~100 K for TiS2 after the compression, suggesting that substantial potential disorder was produced by the high-pressure compression. The significant decrease of |S| could originate from the possible compositional disorder in the GBs of TiS2 after compression. The thermoelectric figure of merit of TiS2 decreased after the compaction due to the large decrease in |S| and increase in ρ, indicating that high-pressure compression is not beneficial to the thermoelectric performance of TiS2.
author2 School of Materials Science & Engineering
author_facet School of Materials Science & Engineering
Hng, Huey Hoon
Li, D.
Qin, X. Y.
Li, H. J.
Zhang, J.
format Article
author Hng, Huey Hoon
Li, D.
Qin, X. Y.
Li, H. J.
Zhang, J.
author_sort Hng, Huey Hoon
title The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
title_short The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
title_full The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
title_fullStr The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
title_full_unstemmed The effects of high-pressure compression on transport and thermoelectric properties of TiS2 at low temperatures from 5 to 310K
title_sort effects of high-pressure compression on transport and thermoelectric properties of tis2 at low temperatures from 5 to 310k
publishDate 2014
url https://hdl.handle.net/10356/101832
http://hdl.handle.net/10220/18825
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