High spin polarization and half-metallic ferromagnetism in novel Half–Heusler FeCrX (X = S, Se and Te) alloys using first-principles calculations

Abstract

First-principles computations using the density functional theory are used to explore the structural, opto-electronic, magnetic, and thermoelectric properties of new predicted half-Heusler FeCrS (X = S, Se, and Te) materials. Two methods are used for estimating the correlation-exchange potential: generalized-gradient approximation GGA and modified Becke-Johnson Tb-mBJ. Furthermore, the examined half-Heusler are mechanically stable, and both show negative formation energy, indicating the prospect of synthesis and stabilization. Additionally, the structural characteristics are looked into for nonmagnetic and ferromagnetic states. The electronic band structure reveals that a band gap of 1.12, 0.89, and 0.86 eV has been found for FeCrS, FeCrSe, and FeCrTe, respectively, for the spin-down channel. For each of these alloys, the Curie temperature has also been determined. The optical parameters show that all compounds have absorption in the UV–visible regions, which shows that these materials are good contenders for optoelectronic and solar cell applications. The thermoelectric characteristics are computed against chemical potential. Due to the higher value of Seebeck coefficient, power factor, figure of merit, and electrical conductivity, FeCrTe is the best material for transport applications.