Systematic investigation of magnetic, optical and transport properties of RTX (R = Rare earth, T = 3d/4d and X = p-block elements) for thermoelectric applications

Abstract

The half-Heusler compounds have been extensively studied because of their exceptional transport properties. We have explored rare earth (RE)-based half-Heusler bismuthides compounds, [Formula: see text]PdBi ([Formula: see text][Formula: see text]=[Formula: see text]Gd, Dy and Ho) with the cubic crystal structure. Structural, magnetic, optical and transport properties are investigated using PBE-GG approximations by solving exchange-correlation potential. Electronic properties including spin-polarized band structure and density of states verified that semimetals with half-filled [Formula: see text]-orbitals across the Fermi-level are useful for thermoelectric applications. Magnetic properties reveal that values of the total spin magnetic moment are in close agreement with the experimental data. Optical properties with spin–orbit coupling (SOC) have a higher absorption coefficient and comparatively lesser energy loss which shows that studied materials are appropriate for optoelectronic devices. Moreover, transport properties including electrical and thermal conductivities, Seebeck coefficient, specific heat, power factor and figure of merit have been discussed in detail. The consistency of our results with the literature reveals that SOC plays a vital role in the transport properties of the materials.