First-principles study of graphene adsorbed on WS2 monolayer

Abstract

We perform first-principles calculations to study the energetics and electronic properties of graphene adsorbed on WS2 surface (G/WS2). We find that the graphene can be bound to WS2 monolayer with an interlayer spacing of about 3.9 ´Å with a binding energy of −21–32 meV per carbon atom dependent on graphene adsorption arrangement, suggesting a weak interaction between graphene and WS2. The nearly linear band dispersion character of graphene can be preserved in G/WS2 system, with a sizable band gap, depending on graphene stacking patterns on WS2 and the distance between graphene and WS2 monolayer. More interestingly, when the interlayer spacing is larger than 3.0 ´Å, the energy-gap opening is mainly determined by the distortion of the isolated graphene peeled from WS2 surface, independent on the WS2 substrate. Further tight-binding model analysis demonstrates that the origin of semiconducting properties can be well understood by the variation of on-site energy of graphene induced by WS2 substrate.

Quantum spin Hall states in graphene interacting with WS2 or WSe2

“…21. Due to this weak interaction (physisorption), a small band gap of about 1 meV is obtained, see the zoomed view in Fig.…”

Bidirectional heterostructures consisting of graphene and lateral MoS2/WS2 composites: a first-principles study

“…The calculated E b of G-WS 2 is À26.9 meV per C atom, which is nearly identical to previously reported values based on the GGA-PBE function (À26.8 meV and À29 meV). 15,55 The E b of G-MoS 2 is À10.2 meV per C atom, which is smaller than the value (À23 meV) reported by Ma et al based on local density approximation (LDA) calculations, 16 which is not surprising given that the LDA method overestimates the calculated results. The binding energies of graphene with (MoS 2 ) 1 /(WS 2 ) 3 , (MoS 2 ) 2 /(WS 2 ) 2 , and (MoS 2 ) 3 /(WS 2 ) 1 lateral heterostructures were À24.1, À18.9, and À14.4 meV, respectively.…”

“…Graphene exhibits a small wrinkle ($0.1 A) in its planar atomic framework for all G-(MoS 2 ) X /(WS 2 ) 4ÀX heterostructures, similar to the previous calculation. 16,26,55 Fig . 4 shows the calculated…”

Novel electronic properties in silicene on MoSe2 monolayer: An excellent prediction for FET

“…For graphene, several 2D semiconductor or insulator substrates (such as BN [17], MoS 2 [18], C 3 N 4 [19] and WS 2 [20]) have been proposed to support it, suggesting potential applications in graphene-based field effect transistors (FETs). Motivated by this idea, Liu et al [21] investigated silicene deposition on two kinds of semiconductor substrates, hexagonal boron nitride (h-BN) and SiC(0001) surface, and found that the silicene-substrate interaction were energetically in the range of 0.067e0.089 eV per Si atom, within the intensity of typical van der Waals interaction.…”

“…However, the complicated surface reconstructions of silicene originated from the interaction with the metal substrate often lead to the deformation of configuration for silicene, which can destroy the Dirac feature of FSS [15,16] with the lower carrier mobility and it would hamper the applications of silicene in electronic nanodevices. For graphene, several 2D semiconductor or insulator substrates (such as BN [17], MoS 2 [18], C 3 N 4 [19] and WS 2 [20]) have been proposed to support it, suggesting potential applications in graphene-based field effect transistors (FETs). Motivated by this idea, Liu et al [21] investigated silicene deposition on two kinds of semiconductor substrates, hexagonal boron nitride (h-BN) and SiC(0001) surface, and found that the silicene-substrate interaction were energetically in the range of 0.067e0.089 eV per Si atom, within the intensity of typical van der Waals interaction.…”