Uranium-based materials for thermoelectric applications

Abstract

Uranium-based compounds possess several properties which make them suitable candidates for thermoelectric applications—complex crystal structures made of heavy components, electrons with enhanced effective masses, as well as low thermal conductivity. However, the difficulty in predicting their properties by computational means, coupled with the lack of experimental investigations on these peculiar systems, limits our understanding of the effect of 5f- and conduction electron hybridization on the Seebeck coefficient, as well as electric and thermal conductivities. In this work, we examine a family of uranium-based materials with a crystal structure of the ternary Zintl phase Y3Au3Sb4. The thermoelectric properties of U3T3Sb4 (T = Ni, Pd, and Pt) compounds are highly dependent upon their microstructures and compositions, arising from the differences in their synthesis. The maximum value of the thermoelectric figure of merit ZT≈0.02 was obtained for the U3Pt3Sb4 compound in the −100 °C ≤T≤ 100 °C temperature range, which makes this material interesting for further development in aerospace applications.