First principles prediction of 2D SiGeP4 monolayer: electronic properties investigation

Abstract

Since the discovery of graphene in 2004, two-dimensional (2D) materials have attracted broad interest due to their outstanding electronic and optical properties. In 2014, a new carbon allotrope named penta-graphene ids theoretically was predicted. The advent of penta-graphene inspired various explorations for new pentagonal 2D nanostructures. In this paper, by using the first- principles calculations based on the density functional theory as implemented in Wien2K, Quantum Espresso, and Material Studio codes, a new two- dimensional pentagonal SiGeP2 monolayer is predicted. The structural, kinetic, and thermal stabilities of the newly found monolayer are evaluated and confirmed by cohesive energy computation, phonon dispersion calculation, and first- principles molecular dynamics simulations, respectively. The electronic properties investigations reveal that the predicted monolayer has a strain tunable indirect bandgap of 2.95 calculated by the GGA-PBE level of theory. Through, the presence of a narrow phonon bandgap between acoustic and optical modes suggests its application in electro-mechanical resonators.

Keywords

• 2d nano structure
• sigep4
• indirect semiconductor
• phonon dispersion