High-Pressure Synthesis of Skutterudite-Type Thermoelectric Materials
We have developed a manufacturing system by combination of high-pressure synthesis method using a multi-anvil press, and spark plasma sintering (SPS) method. By means of the system, we have succeeded in synthesizing new filled skutterudite-type thermoelectric materials MmxCo4Sb12 (Mm=mischmetal). The thermoelectric properties of partially filled skutterudite compounds MmxCo4Sb12 synthesized under high pressure have been investigated. The Seebeck coefficient of MmxCo4Sb12 shows negative value, which means n-type conductivity. The highest dimensionless figure of merit ZT value is 0.25 for Mm0.6Co4Sb12 at 700 K.
C. Sommitsch, M. Ionescu, B. Mishra, E. Kozeschnik and T. Chandra
C. Sekine, H. Kato, Y. Kawamura, C. H. Lee, "High-Pressure Synthesis of Skutterudite-Type Thermoelectric Materials", Materials Science Forum, Vol. 879, pp. 1737-1742, 2017