Thermoelectric Properties of the Pseudogap Fe2VAl System
While the Heusler-type Fe2VAl compound exhibits a semiconductor-like behavior in electrical resistivity, doping of quaternary elements causes a sharp decrease in the low-temperature resistivity ρ and a large enhancement in the Seebeck coefficient S. Substantial enhancement in S can be explained on the basis of the electronic structure where the Fermi level shifts slightly from the center of a pseudogap either up- or downward depending on doping. In particular, a slight substitution of Si for Al leads to a large power factor (P = S2/ρ) of 5.5×10-3 W/m K2 at around room temperature.
S.-G. Kang and T. Kobayashi
Y. Nishino, "Thermoelectric Properties of the Pseudogap Fe2VAl System", Materials Science Forum, Vols. 449-452, pp. 909-912, 2004