Thermoelectric properties of the brownmillerite oxide Ca2-yLayCo2-xAlxO5

Wataru Kobayashi, Akira Satake, Ichiro Terasaki

    研究成果: Article

    11 引用 (Scopus)

    抄録

    We prepared the brownmillerite oxide Ca2-yLayCo2-xAlxO5 and found that it was an n-type conductor. The thermopower and the resistivity of the single crystal are respectively -90 μ V/K and 68 mΩcm along the ab direction at 440 K, which suggest relatively good thermoelectrical properties, compared with other transition-metal oxides. Their temperature dependences are of activation type, and the activation energies are 0.2 eV for the resistivity and 0.04 eV for the thermopower. These energies differ by one order in magnitude, which implies that a polaron dominates the charge transport. The sign of the thermopower of the polycrystals changes from negative to positive at 500 K, indicating that holes are excited thermally to decrease the magnitude of thermopower.

    元の言語English
    ページ(範囲)3025-3028
    ページ数4
    ジャーナルJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
    41
    発行部数5 A
    出版物ステータスPublished - 2002 5

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    Thermoelectric power
    electrical resistivity
    Oxides
    oxides
    polycrystals
    metal oxides
    conductors
    transition metals
    activation
    activation energy
    temperature dependence
    single crystals
    Polycrystals
    Transition metals
    Charge transfer
    Activation energy
    Chemical activation
    Single crystals
    energy
    Temperature

    ASJC Scopus subject areas

    • Physics and Astronomy (miscellaneous)

    これを引用

    Thermoelectric properties of the brownmillerite oxide Ca2-yLayCo2-xAlxO5. / Kobayashi, Wataru; Satake, Akira; Terasaki, Ichiro.

    :: Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers, 巻 41, 番号 5 A, 05.2002, p. 3025-3028.

    研究成果: Article

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