Modeling the Thermoelectric Properties of Ti5O9 Magnéli Phase Ceramics

Published

Journal Article

© 2016, The Minerals, Metals & Materials Society. Magnéli phase Ti5O9 ceramics with 200-nm grain-size were fabricated by hot-pressing nanopowders of titanium and anatase TiO2 at 1223 K. The thermoelectric properties of these ceramics were investigated from room temperature to 1076 K. We show that the experimental variation of the electrical conductivity with temperature follows a non-adiabatic small-polaron model with an activation energy of 64 meV. In this paper, we propose a modified Heikes-Chaikin-Beni model, based on a canonical ensemble of closely spaced titanium t2g levels, to account for the temperature dependency of the Seebeck coefficient. Modeling of the thermal conductivity data reveals that the phonon contribution remains constant throughout the investigated temperature range. The thermoelectric figure-of-merit ZT of this nanoceramic material reaches 0.3 K at 1076 K.

Full Text

Duke Authors

Cited Authors

  • Pandey, SJ; Joshi, G; Wang, S; Curtarolo, S; Gaume, RM

Published Date

  • November 1, 2016

Published In

Volume / Issue

  • 45 / 11

Start / End Page

  • 5526 - 5532

International Standard Serial Number (ISSN)

  • 0361-5235

Digital Object Identifier (DOI)

  • 10.1007/s11664-016-4762-4

Citation Source

  • Scopus