| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a novel material excellent as a thermoelectric conversion material having a big Seebeck coefficient. <P>SOLUTION: The cerium sulfide sintered compact prepared from a Ce<SB>2</SB>S<SB>3</SB>powder of α phase or a powdered raw material obtained by converting the powder into β single phase has a crystal structure of the mixed phase of β and γ, and a Seebeck coefficient of not less than 1000 (μV/K) at 60°C. The mixed phase of β and γ is formed by putting an α phase Ce<SB>2</SB>S<SB>3</SB>powdered raw material having an oxygen concentration of 0.9-1.7 mass% and a carbon impurity concentration of not greater than 0.1 mass%, or a powdered raw material converted into β single phase by heating the powder in vacuum, into a carbon-made mold the inner surface of which is covered with hexagonal lamellar boron nitride (h-BN), and sintering under pressure at 1,600-2,000 K in vacuum for within such a treatment time as the β phase is not extinguished. <P>COPYRIGHT: (C)2008,JPO&INPIT |
