Influence of Antisite Defects on the Thermoelectric Properties of Fe2VAl. Issue 4 (2nd October 2017)

• Record Type: Journal Article
• Authors: Bandaru, Subrahmanyam; Katre, Ankita; Carrete, Jesús; Mingo, Natalio; Jund, Philippe
• Is Part Of: Nanoscale and microscale thermophysical engineering. Volume 21:Issue 4(2017)
• Page Start: 237
• Page End: 246
• Publication Date: 2017-10-02
• Subjects: ab initio calculations -- defects -- Fe2VAl -- Heusler compounds -- thermoelectrics; Heat -- Transmission -- Periodicals; Heat -- Transmission; Electronic journals; Periodicals; 621.402
• DOI: 10.1080/15567265.2017.1355948
• Languages: English
• ISSNs: 1556-7265

Abstract

ABSTRACT: Fe2 VAl is well known as a promising candidate for thermoelectric applications due to its sharp pseudogap at the Fermi level. However, its energy conversion performance is compromised by its high thermal conductivity. Our previous studies revealed that antisite defects like AlV, AlFe, and VAl are the most likely imperfections in Fe2 VAl [1]. It is thus important to understand the electron and phonon transport properties in these defective crystals to estimate their thermoelectric efficiency. Here we analyze the electronic transport properties of Fe2 VAl solid solutions based on Boltzmann transport theory within the constant relaxation time approximation. We then calculate the lattice thermal conductivity of Fe2 VAl containing AlV antisite defects by solving the linearized Boltzmann transport equation based on an ab initio model for defects. We find a significant increase of around an order of magnitude in ZT at 300 K compared to the stoichiometric compound.