Thermoelectric Properties of CeFe3CoSb12-FeSb2 Composite

Abstract

We have prepared a sintered CeFe3CoSb12-FeSb2 composite and investigated the Seebeck coefficient, electrical resistivity, and thermal conductivity in order to estimate the corresponding figure of merit. The thermal conductivity of the composite whose molar ratio of CeFe3CoSb12 to FeSb2 is 0.9:0.1 is as large as that of CeFe3CoSb12 while the lattice contribution of the thermal conductivity of the composite is somewhat smaller than that of CeFe3CoSb12, which is ascribed to the enhancement of the phonon scattering caused by the additive material. With increasing FeSb2 content the thermal conductivity of the composite is enhanced. The Seebeck coefficient and electrical resistivity of the composite generally decrease with increasing FeSb2 content. These behaviors in the thermal conductivity, Seebeck coefficient and electrical resistivity with increasing FeS2 content is considered to be ascribed to the physical properties of FeSb2. As a result, the composite whose molar ratio of CeFe3CoSb12 to FeSb2 is 0.9:0.1 shows somewhat larger figure of merit than CeFe3CoSb12 in the whole temperature range from 373K to 773K.