Development of thermoelectric materials fabricated by spark plasma sintering methods

We study the thermoelectric properties of some candidates of high performance thermoelectric materials that are fabricated by the spark plasma sintering technique. The first topic is concerned with preparation of higher density samples of zinc antimony compound Zn ₄Sb ₃ for which it is known that fabrication of high density samples is a key point to improve the thermoelectric performance. The second topic is concerned with reducing of grain sizes of sintered samples to decrease the thermal conductivity. The third topic is concerned with the new approach combining the experiment and the theory for magnesium silicide Mg ₂Si. It is one of a good thermoelectric material with the simple crystal structure. Therefore the material is the appropriate material as a test bed of the theoretical method based on the ab-initio electronic structure method.