The Potential of FeVSb Half-Heusler Phase for Practical Thermoelectric Material

The electronic structure and electron transport properties of FeVSb half-Heusler phase were calculated using first-principles calculations and Boltzmann transport equation. We found, as a result of theoretical calculations, that the magnitude of the dimensionless of figure of merit (ZT) could be increased up to ∼0.84 due to the drastic increase of the power factor when the carrier concentration of p-type FeVSb is optimized through element substitution to vary the valence electron concentration. We revealed that this large increase in ZT is closely related to the significant variations both in electronic density of states and spectral conductivity with decreasing energy at the top of the valence band.