Sodium-based di-chalcogenide: a promising material for tandem solar cells

• Published in: Electronic Structure Vol. 6; no. 1; pp. 15013 - 15020
• Main Authors: Gómez-Ríos, Danilo, Pérez-Walton, S, López-Giraldo, F E, Peralta, J, Espinosa-García, W F
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.03.2024
• Subjects: DFT; Di-chalcogenide; GoWo; NaNbS; PBEsol
• ISSN: 2516-1075; 2516-1075
• DOI: 10.1088/2516-1075/ad2f5b

Abstract Compounds based on chalcogen elements are widely studied currently due to their many interesting applications for electronic devices. The sodium-based dichalcogenide (NaNbS 2 ) is a fascinating material with storage and conversion energy applications. In this paper, we conduct a first-principles investigation of the structural and thermodynamic stability and electronic properties of this material. We analyze a total of four structures to find the ground state using a fourth-order Birch–Murnaghan equation of state: the α and η related to the A-phase and the ζ 1 and ζ 2 related to the B-phase. We carefully address the exchange-correlation effects using the semi- local GGA-PBEsol targeted for solids. To analyze the electronic structure with higher accuracy, we implement the quasi-particle G o W o approximation. Our results for the fourth-order Birch–Murnaghan equation show that the most thermodynamically stable phase at zero temperature is α . To provide experimentalists insights about the possible routes to grow these materials, we calculated the convex hull of the α -model and ζ 1 -model, finding that both are energetically stable. Finally, the calculated band gap with quasiparticle corrections for the α -model is 1.03 eV, which suggests possible applications of this material as a bottom cell in modern solar cells.