Investigation of new two-dimensional materials derived from stanene

Abstract

In this study, we have explored new structures which are derived from stanene. In these new proposed structures, half of the Sn atoms, every other Sn atom in two-dimensional (2D) buckled hexagonal stanene structure, are replaced with a group-IV atom, namely C, Si or Ge. So, we investigate the structural, electronic and optical properties of SnC, SnGe and SnSi by means of density functional theory based firstprinciples calculations. Based on our structure optimization calculations, we conclude that while SnC assumes almost flat structure, the other ones have buckled geometry like stanene. In terms of the cohesive energy, SnC is the most stable structure among them. The electronic properties of these structures strongly depend on the substituted atom. We found that SnC is a large indirect band gap semiconductor, but SnSi and SnGe are direct band gap ones. Optical properties are investigated for two different polarization of light. In all structures considered in this study, the optical properties are anisotropic with respect to the polarization of light. While optical properties exhibit features at low energies for parallel polarization, there is sort of broad band at higher energies after 5 eV for perpendicular polarization of the light. This anisotropy is due to the 2D nature of the structures.

Bonding, structure, and mechanical stability of 2D materials: the predictive power of the periodic table

“…Table 4 provides the cohesive energies and structural data of the planar group IV carbides SiC, [112][113][114][115][116][117] GeC, 115,[118][119][120] and SnC 115,121,122 and the buckled monolayers SiGe, 115,123,124,128 SnSi, 115,122,125,126 and SnGe. 115,122,125,126 The dependence of the cohesive energy on bond length of these binary compounds is displayed in Fig. 13(a).…”

Topological phase transition in quantum-heat-engine cycles

“…Stanene is a counterpart of graphene for tin atoms [28][29][30] with low-buckled honeycomb geometry [31]. In contrast to graphene it has a larger spin-orbit coupling [32,33], can host the quantum spin Hall effect at room temperature for dissipationless electric currents [29], and its band structure, in particular, Dirac cone band gap, can be controlled with an out-ofplane electric field such that it exhibits a TPT between two-dimensional trivial and topological insulator (2DTI) phases depending on the applied electric field [27,[34][35][36]. 2D Sn has been fabricated recently by molecular beam epitaxy [37].…”

Electron-Driven In Situ Transmission Electron Microscopy of 2D Transition Metal Dichalcogenides and Their 2D Heterostructures

“…Bulk TMDs can therefore be exfoliated to single or few layers. − The isolation of a suspended MoS 2 monolayer was first achieved in 1986 . This was driven by the discovery of graphene in 2004 by Novoselov and Geim after which our curiosity to find other single atom and single unit cell thick two-dimensional (2D) materials started in earnest. − Since then, the level of interest in TMDs has grown massively for both fundamental studies as well as their significant promise in numerous application areas such as microelectronics, , batteries, − solar cells, , sensors, − and biomedicine. − TMDs comprise a metal layer sandwiched between two chalcogen layers . As illustrated in Figure a, the plane containing the metal atoms is located between two planes of chalcogen atoms, forming a hexagonal arrangement, which can be trigonal prismatic or octahedral.…”