Physical properties of ternary thallium chalcogenes T1(2)MQ(3) (M = Zr, Hf; Q = S, Se, Te) via ab-initio calculations

ATEŞER E., Okvuran O., ÇİFTCİ Y., ÖZIŞIK H., DELİGÖZ E.

CHINESE PHYSICS B, cilt.28, sa.10, 2019 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 28 Sayı: 10
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1088/1674-1056/ab4127d
  • Dergi Adı: CHINESE PHYSICS B
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Gazi Üniversitesi Adresli: Evet

Özet

We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes T1(2)MQ(3) (M = Zr, Hf; Q = S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, T1(2)ZrTe(3) and T1(2)HfTe(3) can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second -order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications (ZT similar to 0.9).