Computational insights into structural, electronic, and optical properties of Janus GeSO monolayer

• Published in: RSC advances Vol. 11; no. 45; pp. 28381 - 28387
• Main Authors: Do, Thi-Nga, Hieu, Nguyen N, Poklonski, N. A, Thanh Binh, Nguyen Thi, Nguyen, Cuong Q, Hien, Nguyen D
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 16.08.2021; The Royal Society of Chemistry
• Subjects: Absorption spectra; Chemistry; Density functional theory; Elastic properties; Germanium oxides; Luminous intensity; Mathematical analysis; Modulus of elasticity; Monolayers; Optical properties; Physical properties; Two dimensional materials
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d1ra05424d

Although O is an element of chalcogen group, the study of two-dimensional (2D) O-based Janus dichalcogenides/monochalcogenides, especially their 1T-phase, has not been given sufficient attention. In this work, we systematically investigate the structural, electronic, and optical properties of 1T Janus GeSO monolayer by using the density functional theory. Via the analysis of phonon spectrum and evaluation of elastic constants, the GeSO monolayer is confirmed to be dynamically and mechanically stable. Calculated results for the elastic constants demonstrate that the Janus GeSO monolayer is much mechanically flexible than other 2D materials due to its small Young's modulus. At the ground state, while both GeS 2 and GeO 2 monolayers are indirect semiconductors, the Janus GeSO monolayer is found to be a direct band gap semiconductor. Further, effective masses of both electrons and holes are predicted to be directionally isotropic. The Janus GeSO monolayer has a broad absorption spectrum, which is activated from the visible light region and its absorption intensity is very high in the near-ultraviolet region. The calculated results not only systematically provide the fundamental physical properties of GeSO monolayer, but also stimulate scientists to further studying its importance both theoretically and experimentally. Although O is an element of chalcogen group, the study of two-dimensional (2D) O-based Janus dichalcogenides/monochalcogenides, especially their 1T-phase, has not been given sufficient attention.