Advertisement

Journal of Electronic Materials

, Volume 43, Issue 6, pp 2430–2434 | Cite as

Reinvestigation of Thermoelectric Properties of n- and p-Type Ba8−d Au x Si46−xy Clathrate

  • Shinji Munetoh
  • Makoto Saisho
  • Takuya Oka
  • Toshiko Osada
  • Hideshi Miura
  • Osamu Furukimi
Article

Abstract

We have synthesized n- and p-type clathrates Ba8−d Au x Si46−xy with various Au contents (4.6 < x < 6.0) by arc-melting, annealing at 1173 K, and spark plasma sintering at 1073 K. The Au compositions found by wavelength-dispersive x-ray spectrometry for the synthesized samples were slightly lower than the nominal compositions. Ba7.8Au4.6Si41.4 and Ba7.7Au4.9Si41.1 samples showed n- and p-type conduction, respectively. According to the electron count (Ba2+)8Au(3−)5.33Si40.67, the clathrate composition with x = 5.33 is expected to be an intrinsic semiconductor. Our experimental results show that increase of the Au composition causes a transition from n-type to p-type conduction between x = 4.6 and 4.9. We have also calculated the band structures of the Ba8Au x Si46−x clathrate including a vacancy by ab initio calculation based on density functional theory with structure optimization. It was found that the vacancy behaves like an electron acceptor and the numbers of vacancies at 24k sites for the synthesized Ba8Au x Si46−xy clathrates can be estimated as ∼0.4 in a unit cell.

Keywords

Thermoelectric properties Ba-Au-Si clathrate vacancy spark plasma sintering ab initio calculation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    B. Poudel, Q. Hao, Y. Ma, Y.C. Lan, A. Minnich, B. Yu, X.A. Yan, D.Z. Wang, A. Muto, D. Vashaee, X.Y. Chen, J.M. Liu, M.S. Dresselhaus, G. Chen, and Z.F. Ren, Science 320, 634 (2008).CrossRefGoogle Scholar
  2. 2.
    S. Yamanaka, E. Enishi, H. Fukuoka, and M. Yasukawa, Inorg. Chem. 39, 56 (2000).CrossRefGoogle Scholar
  3. 3.
    J.L. Cohn, G.S. Nolas, V. Fessatidis, T.H. Metcalf, and G.A. Slack, Phys. Rev. Lett. 82, 779 (1999).CrossRefGoogle Scholar
  4. 4.
    C. Cros, M. Pouchard, and P. Hagenmuller, J. Solid State Chem. 2, 570 (1970).CrossRefGoogle Scholar
  5. 5.
    H. Anno, H. Yamada, T. Nakabayashi, M. Hokazono, and R. Shirataki, J. Solid State Chem. 193, 94 (2012).CrossRefGoogle Scholar
  6. 6.
    H. Anno, M. Hokazono, R. Shirataki, and Y. Nagami, J. Mater. Sci. 48, 2846 (2013).CrossRefGoogle Scholar
  7. 7.
    N. Mugita, Y. Nakakohara, R. Teranishi, and S. Munetoh, J. Mater. Res. 26, 1857 (2011).CrossRefGoogle Scholar
  8. 8.
    G. Cordier and P. Woil, J. Less-Common Met. 169, 291 (1991).CrossRefGoogle Scholar
  9. 9.
    I. Zeiringer, M.X. Chen, A. Grytsiv, E. Bauer, R. Podloucky, H. Effenberger, and P. Rogl, Acta Mater. 60, 2324 (2012).CrossRefGoogle Scholar
  10. 10.
    N. Jaussaud, P. Gravereau, S. Pechev, B. Chevalier, M. Menetrier, P. Dordor, R. Decourt, G. Goglio, C. Cros, and M. Pouchard, C. R. Chimie 8, 39 (2005).CrossRefGoogle Scholar
  11. 11.
    C. Candolfi, U. Aydemir, M. Baitinger, N. Oeschler, F. Steglich, and Y. Grin, J. Appl. Phys. 111, 043706 (2012).CrossRefGoogle Scholar
  12. 12.
    U. Aydemir, C. Candolfi, A. Ormeci, Y. Oztan, M. Baitinger, N. Oeschler, F. Steglich, and Y. Grin, Phys. Rev. B 84, 195137 (2011).CrossRefGoogle Scholar
  13. 13.
    M. Saisho, L. Bin, Y. Nagatomo, Y. Nakakohara, R. Teranishi, and S. Munetoh, J. Phys. 379, 012009 (2012).Google Scholar

Copyright information

© TMS 2014

Authors and Affiliations

  • Shinji Munetoh
    • 1
  • Makoto Saisho
    • 1
  • Takuya Oka
    • 1
  • Toshiko Osada
    • 2
  • Hideshi Miura
    • 2
  • Osamu Furukimi
    • 1
  1. 1.Department of Materials Science and EngineeringKyushu UniversityFukuokaJapan
  2. 2.Department of Mechanical EngineeringKyushu UniversityFukuokaJapan

Personalised recommendations