Transport phenomena of TiCoSb : defect induced modification in the structure and density of states
|Author:||Mahakal, S.1; Das, Diptasikha2; Singha, Pintu3;|
1Department of Physics, Vidyasagar Metropolitan College, Kolkata-700006, India
2Department of Physics, ADAMAS University, Kolkata-700126, India
3Department of Physics, University of Calcutta, Kolkata-700009, India
4Department of Physics, Tamkang University, New Taipei City-251301, Taiwan
5Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 Barrackpore Trunk Road, Kolkata-700 108, India
6Nano and Molecular Systems Research Unit (NANOMO), University of Oulu, Oulu, Finland
|Online Access:||PDF Full Text (PDF, 2.4 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe20231012139890
Royal Society of Chemistry,
|Publish Date:|| 2023-10-12
TiCoSb1+x (x = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.06) samples have been synthesized, employing solid state reaction method followed by arc melting. Theoretical calculations, using density functional theory (DFT), have been performed to estimate the band structure and density of states (DOS). Further, energetic calculations using first principles have been carried out to reveal the formation energy for vacancy, interstitial and anti-site defects. A detailed structural calculation, employing Rietveld refinement, reveals the presence of embedded phases, vacancies, and interstitial atoms, which is also supported by theoretical calculations. Lattice strain, crystalline size, and dislocation density have been estimated by Williamson–Hall and modified Williamson–Hall methods. Thermal variation of resistivity [ρ(T)] and thermopower [S(T)] have been explained using the Mott equation and density of states (DOS) modification near the Fermi surface due to a Co vacancy and embedded phases. Figure of merit (ZT) has been calculated and a ZT for TiCoSb 4 to 5 times higher than earlier reported values was obtained at room temperature.
|Pages:||4168 - 4179|
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
116 Chemical sciences
This work is supported by the Science and Engineering Research Board (SERB), Government of India, in the form of sanctioning research project (File Number: EEQ/2018/001224). We acknowledge UGC DAE CSR, Kolkata, for providing arc melting facilities. Author SM is thankful to CSIR, India for providing Research Fellowships (File Number: 08/463(0002)/2019-EMR-I).
© 2023 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.