## 抄録

We report structural, magnetic and high-temperature thermoelectric properties of Delafossite-type oxide, CuCr_{1-x}Mg_{x}O _{2} (0≤×0.05). Lattice parameter, c, linearly decreases with increasing Mg concentration in the range, 0≤ × <0.03. This decrease is mainly caused by the shrinking of O-Cu-O dumbbells which connect the CdI _{2}-type (Cr/Mg)O_{2} slabs. Magnetic susceptibility measurements indicate that Cr^{3+} is in the high spin state in the paramagnetic phase above 25 K. Electrical resistivity, ρ, of CuCr _{1-x}Mg_{x}O_{2} exhibits semiconducting behavior (dp/dT<0) in the range from 350 K to 1100 K and becomes lower through the partial substitution of Mg^{2+} for Cr_{3+} in 0≤×≤0.03. Due to positive Seebeck coefficients, S, of these oxides, it is natural to assume that the dominant charge carriers of CuCr _{1-x}Mg_{x}O_{2} are positive holes. Experimental values of Sat 1100 K have consistency with the theoretical values predicted from Koshibae's formula. From the linear S vs. lnσ plot, it is estimated that the observed power factor, S^{2}σ, reaches the maximum value around x=0.03 in this system. The thermal conductivity, Κ, for CuCr _{1-x}Mg_{x}O_{2} ranges from 6 to 10 W·m _{-1}·K^{-1} at 300 K. The maximum dimensionless figure of merit, ZT=S^{2}T/ρΚ, of the sample with x=0.03 is 0.04 at 950 K.

本文言語 | English |
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ホスト出版物のタイトル | Proceedings ICT'06 - 25th International Conference on Thermoelectrics |

ページ | 92-96 |

ページ数 | 5 |

DOI | |

出版ステータス | Published - 2006 |

外部発表 | はい |

イベント | ICT'06 - 25th International Conference on Thermoelectrics - Vienna, Austria 継続期間: 2006 8月 6 → 2006 8月 10 |

### 出版物シリーズ

名前 | International Conference on Thermoelectrics, ICT, Proceedings |
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### Other

Other | ICT'06 - 25th International Conference on Thermoelectrics |
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国/地域 | Austria |

City | Vienna |

Period | 06/8/6 → 06/8/10 |

## ASJC Scopus subject areas

- 工学（全般）

## フィンガープリント

「Structural, magnetic and thermoelectric properties of Delafossite-type oxide, CuCr_{1-x}Mg

_{x}O

_{2}(0 ≤ × ≤ 0.05)」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。