ICT2014 Abstracts

Nanostructured degenerate n-type bulk Mg₂(Si,Sn) solid solutions are promising candidates for power generation at intermediate temperature ranges since the elements are abundant, inexpensive, and environmentally harmless, compared to those in conventional Pb and Te based thermoelectric materials. The thermoelectric figure of merit (ZT) of Mg₂(Si,Sn) is decent but inferior to the state-of-the-art Pb-Te based materials, mainly due to relatively high phononic (or lattice) thermal conductivity. In this work, we added nanoparticles to the solid solutions so as to further suppress the lattice contribution of thermal conductivity. Bulk materials were synthesized by using high energy ball milling and DC assisted hot press methods for facile synthesis and small grain sizes resulted from fast sintering processes. Nanoparticles reduced thermal conductivity, and the influence of size, material, and concentration of nanoparticles on thermal conductivity was investigated.