First Principle Study and Optimal Doping for High Thermoelectric Performance of TaXSn Materials (X = Co, Ir and Rh)

Authors A. Khaldi1, Y. Benallou1, M. Zemouli2, K. Amara2, M. El Keurti2

1Technology Laboratory of Communication, University of Saida -Moulay Tahar, 20000 Saïda, Algeria

2Laboratory of Physico-chemical studies, University of Saida - Dr. Moulay Tahar, 20000 Saïda, Algeria

Issue Volume 13, Year 2021, Number 1
Dates Received 10 January 2021; revised manuscript received 15 February 2021; published online 25 February 2021
Citation A. Khaldi, Y. Benallou, et al., J. Nano- Electron. Phys. 13 No 1, 01011 (2021)
PACS Number(s) 72.20.Pa, 61.72.uf, 87.19.rd
Keywords Semiconductors (25) , Thermoelectric performances, GGA-PBEsol, p-type and n-type doping levels, Thermopower factors, Doping level.

In this paper, the full potential linearized augmented plane wave method implemented in the WIEN2K code with first principles-based density functional theory are used to investigate the structural, elastic, electronic and thermoelectric properties of TaCoSn, TaIrSn and TaRhSn. The structural and elastic constants are calculated using the generalized gradient potential developed by Perdew-Burke-Ernzerhof (GGA-PBEsol). The electronic structures are performed by means of GGA-PBEsol and improved by Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. Our results show that the studied compounds are semiconductors with indirect gaps. On the other hand, we investigated the thermoelectric properties at different temperatures with respect to the chemical potential. The results show that the thermopower factors are more important for p-type doping than those for n-type doping and the maximum value of these factors indicates the optimal hole-doping level which gives rise to high thermoelectric performances of these materials. Finally, we note that the best thermopower values are found for the TaRhSn compound with optimal doping levels of (75.76, 175.60 and 238.92)  1014 W cm – 1 K – 2 s – 1 at temperatures of 300, 600, and 900 K, respectively.

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