Prognosis and investigation of the electrical and optical properties of pseudo graphene GeS2 Nano-structure by the method of density functional theory (DFT)

In this paper, the new Nano-structure of Germanium disulfide (GeS2</sub>) was forecasted using Wien2k computing software by the method of density functional theory (DFT). The stability of the nanostructure was confirmed by cohesive energy calculation as well as the phonon dispersion calculation. The results of the simulation approach show that‎ the GeS2</sub> monolayer is an indirect band gap semiconductor with a band gap of about 0.9 eV, which is adjustable by a two-dimensional stretching and strain. Besids, the study of the properties of the optics of GeS2</sub> showes that it has minimal absorption and reflection in the visible region of the electromagnetic spectrum, while the GeS2</sub> in the ultraviolet region of the electromagnetic waves is not only a good absorbent but also has a relatively high reflection. The results of this study suggest that the considered structure (GeS2</sub>) has a good application in the new generation of the opto-electronic devices, especially as a UV protection layer.