DFT study of structural, electronic, magnetic, elastic, and thermoelectric properties of Ta-based half-Heusler alloys CsTaX (X = C, Si, and Ge) for spintronics and thermoelectric technologies

• Published in: Computational and theoretical chemistry 2024-11, Vol.1241, p.114902, Article 114902
• Main Authors: Saleem, Saba, Muhammad, Nawaz, Murtaza, G., Ayyaz, Ahmad, Naeem, Maha, Usman, Ahmad, Aysha, Urwa-tul, Touqir, Maryam
• Format: Article
• Language: English
• Subjects: DFT calculations; Elastic properties; Half metallic ferromagnetic; Half-Heusler; Thermoelectric properties
• ISSN: 2210-271X
• DOI: 10.1016/j.comptc.2024.114902

[Display omitted] •Half Hesuler alloys CsTaX (X = C, Si and Ge) are stable in FM state.•Electronic properties of these alloys confirm the half-metallic nature.•The magnetic moment for CsTaC is 6 μB and for CsTaSi and CsTaGe is 2 μB.•ZT values of 0.99, 0.97, and 0.90 suggest greater performance in thermoelectric devices. The structural, electronic, elastic, magnetic, and thermoelectric characteristics of three novel Ta-based half-Heusler alloys, CsTaC, CsTaSi, and CsTaGe, have been investigated using the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within the density functional theory (DFT). The volume-optimization graphs show that all compounds are stable in the ferromagnetic (FM) phase. Half-Metallicity of these compounds is confirmed by the density of states (DOS) and band structures. The total magnetic moment for CsTaC is 6 μB, and for CsTaX (X = Si, Ge) is 2 μB. The negative pd exchange energy and exchange constants confirm ferromagnetism. The values of Pugh’s ratio (B/G) and Poisson’s ratio (v) reveal that CsTaC is ductile and CsTaX (Si, Ge) is brittle. The thermoelectric response is estimated using the BoltzTraP code, demonstrating that at room temperature, maximum ZT values for CaTaC, CsTaSi, and CsTaGe are 0.99, 0.97, and 0.90, respectively. Consequently, CsTaX (X = C, Si, and Ge) are suitable candidates for spintronic and thermoelectric technologies.