Structural and electronic properties of SnS 2 stacked nanosheets: An ab-initio study

Abstract

We present an ab-initio study of the structural and electronic properties of SnS 2 stacked nanosheets using the standard LDA and GGA functionals as well as the newly developed variants of the non-local van der Waals (vdW) exchange correlation functionals, namely vdW-DF-revPBE and vdW-DF2-C09. We have examined different stacking configurations of the two, three and four SnS 2 layers. The GGA-PBE functional fails to describe the interlayer binding energies and interlayer spacing of SnS 2 nanosheets, while a good agreement is observed between the calculated and available experimental values when the van der Waals corrected functionals are used, mostly the vdW-DF2-C09. It is found that the interlayer interactions in the SnS 2 films are not only vdW type but, the overlap of wave functions of neighboring layers have to be taken into account. We have observed a systematic reduction in the band gap with the increase in the number of stacked layers. This can be another way of controlling the band gap of SnS 2 nanosheets as required for electronic devices.

First-principles analysis of phonon thermal transport properties of two-dimensional WS2/WSe2 heterostructures*

“…The effect of vdW interaction is considered in all simulations with dispersion corrected DFT method (vdW-DF-revPBE), [29] which has been proven reliable for the vertically stacked system. [30] Moreover, we imposed a vacuum spacing larger than 20 Å to avoid the interactions among heterostructures neighboring layers in the periodic slabs. All atoms in the crystals system are fully relaxed until Hellmann-Feynman force on each ion is less than 10 −4 eV• Å−1 .…”

Metallic Metastable Hybrid 1T′/1T Phase Triggered Co,PSnS2 Nanosheets for High Efficiency Trifunctional Electrocatalyst

“…Moreover, SnS 2 , which is earth abundant, safe, inexpensive, and highly chemically stable in a wide pH range, delivers an encouraging catalysis performance and a highly interfacial electronegativity. [24][25][26] In addition, apart from 1T phase, the existence and formation of different phases of SnS 2 in a metastable state have to date only been investigated using theoretical approaches. [27] Many researchers have attempted to develop different phases of TMDs in 1T, 1T′, or combination of 1T and 1T′, which is in a metastable state that exhibits stable and highly active catalysts.…”

Tuning of Electronic and Optical Properties of PtS2 Monolayer Using Stacking Engineering

“…As an illustration, the MoS 2 bandgap changes from indirect to direct when a bulk structure transforms to a monolayer. [13] Monolayers possess several exceptional characteristics, such as the capacity to modify the bandgap by employing the layer thickness, [14] stacking order, [15][16][17][18][19] strain, [20][21][22] and electric field. [23] These could be employed in optoelectronic, spintronic, and valleytronic applications due to their wide range of properties, including excellent mobility, air stability, bandgap tunability, etc.…”