Electrical Transport Properties of Nb and Ga Double Substituted Fe2VAl Heusler Compounds

Resumo

In this work the results of studying the electrical transport properties of Fe₂V_{1 –x}Nb_xAl_{1 –y}Ga_y (0.1 ≤ x ≤ 0.2 and 0.1 ≤ y ≤ 0.2) are presented. The specimens were fabricated using conventional arc-melting method followed by ball milling and spark plasma sintering. It was shown that dual-site substitution approach may lead to a more noticeable changes in the Seebeck coefficient and the electrical resistivity comparing to single-site substitution. Since such substitution can be assumed as isovalent one, the evolution of the electrical transport properties was mainly attributed to the changes in the band gap and charge carrier mobility values. To testify applicability of computational methods on these samples we have used well-known density functional theory and Boltzmann transport equation solving on one of the samples.