Thermoelectric power factor enhancement of textured ferroelectric Sr xBa1-x Nb2O6-δ ceramics

Soonil Lee, Sinan Dursun, Cihangir Duran, Clive A. Randall

Research output: Contribution to journalArticle

32 Scopus citations

Abstract

A promising n-type thermoelectric oxide, based on the tungsten bronze-structured ferroelectric SrxBa1-xNb 2O6-δ (SBN, x̃0.61), was investigated to enhance the thermoelectric power factor through templated grain growth (textured polycrystalline). In the reduced SBN textured, both the electrical conductivity (σ) and the magnitude of thermopower (S) are increased in the c axis: σ33 > σ11 and |S33| > |S11|, and consequently, the thermoelectric power factor (PF) increased significantly due to crystal anisotropy and grain boundary density reduction. It was found in randomly oriented polycrystalline ceramics that the thermoelectric properties are dominated by a-axis properties. A ferroelectric-thermoelectric anomaly is observed at 4mm-4/mmm phase transition temperature (TC) and depends on temperature and reduction degree, consistent with our earlier observations in single crystal SBN. Above TC, the carrier transport mechanism is controlled by polaron hopping conduction, and below TC the behavior depends on the degree of reduction. However, the magnitude of the Seebeck coefficient is dependent on the crystal anisotropy.

Original languageEnglish (US)
Pages (from-to)26-30
Number of pages5
JournalJournal of Materials Research
Volume26
Issue number1
DOIs
StatePublished - Jan 14 2011

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Thermoelectric power factor enhancement of textured ferroelectric Sr <sub>x</sub>Ba<sub>1-x</sub> Nb<sub>2</sub>O<sub>6-δ</sub> ceramics'. Together they form a unique fingerprint.

  • Cite this