Thermoelectric Power in Transition-Metal Monosilicides

抄録

We study, both experimentally and theoretically, temperature and electron-density (band-filling) dependence of Seebeck coefficient in B20-type transition-metal monosilicides to critically study the validity of the Boltzmann transport theory based on the band structure as a guiding principle for the materials design of metallic thermoelectric compounds. The global thermoelectric phase diagram for a wide range of materials (CrSi–MnSi–FeSi–CoSi–Co_0.85Ni_0.15Si and their interpolating solid solutions) is obtained. Theoretical results derived from the calculated band structure can reproduce a global feature of experimental results except the higher temperature region of FeSi, providing the firm basis to understand the systematics of thermoelectricity in metallic compounds including the role of electron correlation and to develop the material design for larger thermoelectricity.