Preparation and low-temperature thermoelectric properties of the composite crystal [Ca2(Co0.65Cu0.35)2 O4]0.624CoO2

Yuzuru Miyazaki, Tatsuro Miura, Yasuhiro Ono, Tsuyoshi Kajitani

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64 Citations (Scopus)


A new composite crystal cobaltite, [Ca2(Co0.65Cu0.35)2 O4]0.624CoO2, has been synthesized and its thermoelectric properties below 300 K have been investigated. The compound consists of a CdI2-type CoO2 conduction sheet and a quadruplicated rock-salt-type [Ca2(Co0.65Cu0.35)2O4] layer alternatively stacked along the c-axis. Metallic conductivity accompanied by large thermoelectric power (S) has been observed down to 100 K. At 300 K, the sample exhibits S = 150 μV·K-1 and resistivity of ρ = 15 mω·cm. The resulting power factor (S2/ρ) becomes 1.5 × 10-4 W·K-2 at 300 K, which is more than 20% larger than the value reported for a polycrystalline sample of another composite crystal, [Ca2CoO3]0.62 CoO2.

Original languageEnglish
JournalJapanese Journal of Applied Physics, Part 2: Letters
Issue number7 B
Publication statusPublished - 2002 Jul 15


  • Calcium cobalt copper oxide
  • Composite crystal
  • Electric resistivity
  • Power factor
  • Thermoelectric power

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy (miscellaneous)
  • Physics and Astronomy(all)


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