LANTHANUM SULFIDE OR CERIUM SULFIDE SINTERED COMPACT AND MANUFACTURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a novel material having a large Seebeck coefficient and therefore suitable as a thermoelectric convertion material. SOLUTION: This sintered compact comprises La2S3 or Ce2S3, having a mixed β-and γ-phase in its crystalline structure and having a Seebeck coefficient larger than that of a single γ-phase. The material is produced by hot-pressing highly purified, pulverized La2S3 in β-phase or Ce2S3 in α-phase controlling the oxygen content in a specified range and suppressing the carbon impurity content in a carbon-made mold where the inner surface is coated with h-BN in vacuum.