The promising potential of half Heusler EuFeSb alloy for high-performance thermoelectric with improved half-metallicity and optical properties: a DFT study

In this study, we have employed the density functional theory to investigate the structural, electronic, optic, and thermoelectric properties of the new Half Heusler EuFeSb alloy. We have explored the structural properties of the EuFeSb alloy and their stability. Our results revealed that the ferromagnetic phase is more favorable and stable when compared to the anti-ferromagnetic one. Furthermore, the electronic properties exhibited a half metallic behavior. In addition, the minority spin configuration presents a semi-conductor behavior with a band gap of 1.106 eV of the Heusler EuFeSb alloy. Additionally, we have explored the optical properties, including its absorption coefficient, refractive index, electron energy loss, and optical conductivity. Indeed, the absorption coefficient shows that the spectrum exhibits a higher value in the ultraviolet region than in the visible region. This characteristic has potential applications in material photocells. Finally, we have carried out the thermoelectric analysis of the Half Heusler EuFeSb alloy using the Boltztrap code. The Seebeck coefficient electrons at T = 250 K reach a minimum value of − 16 µV/K, indicating that the compound is an n-type material due to the negative values of the total Seebeck coefficient. This property of the Heusler EuFeSb alloy allows it to convert a portion of its thermal energy into electrical energy, making it a potential candidate for thermoelectric applications.