A DFT investigation of Al2XS4 (X=Hg, Mg) for energy harvesting applications. (December 2022)

• Record Type: Journal Article
• Authors: Naseem, Mehwish; Aziz, Asima; Aldaghfag, Shatha A.; Misbah, ; Yaseen, Muhammad; Neffati, R.
• Is Part Of: Journal of physics and chemistry of solids. Volume 171(2022)
• Publication Date: 2022-12
• Subjects: Optoelectronic -- Spinel sulfides -- Thermoelectric -- Semiconductors; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2022.110982
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: The full-potential linearized augmented plane wave (FP-LAPW) approach was employed to explore the electronic, structural, thermoelectric (TE) and optical aspects of Al2 HgS4 and Al2 MgS4 cubic spinels. The tolerance factor (τ) for Al2 XS4 (X = Hg, Mg) compounds is 0.9, which revealed the structure of mentioned compounds in cubic phase. Results indicated that Al2 XS4 (X=Hg, Mg) are semiconductors with direct band gap (Eg ) of 2.11 and 3.69 eV, correspondingly at Γ symmetry points. Moreover, In optical properties, The absorption region extends from visible to ultraviolet light, which makes both spinels ideal for optoelectronics devices. Furthermore, the BoltzTrap code was used to investigate thermoelectric (TE) properties, which revealed that as the temperature rises, the thermal conductivity (k/τ), electrical conductivity (σ/τ), and power factor (PF) increase, but the Seebeck coefficient (S) reduced. The magnitude of figure of merit (ZT) is 0.78 and 0.74 for Al2 HgS4 and Al2 MgS4, correspondingly. ZT revealed that studied compounds are suitable for TE devices for the source of energy. Highlights: Al2 HgS4 and Al2 MgS4 are direct band gap (Eg ) semiconductors with Eg of 2.11 and 3.69 eV, respectively. The absorption region extends from visible light to ultraviolet light for both compounds. The magnitude of figure of merit (ZT) is 0.78 and 0.74 for Al2 HgS4 and Al2 MgS4, respectively. ZT revealed that studied compounds are suitable for TE devices for the source of energy.