First-Principles Study of a MoS2-PbS van der Waals Heterostructure Inspired by Naturally Occurring Merelaniite.

Gemechis D Degaga,John A Jaszczak,Sumandeep Kaur,Ravindra Pandey

doi:10.3390/ma14071649

Gemechis D Degaga, John A Jaszczak + Show 2 more

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https://doi.org/10.3390/ma14071649

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Abstract

Vertically stacked, layered van der Waals (vdW) heterostructures offer the possibility to design materials, within a range of chemistries and structures, to possess tailored properties. Inspired by the naturally occurring mineral merelaniite, this paper studies a vdW heterostructure composed of a MoS2 monolayer and a PbS bilayer, using density functional theory. A commensurate 2D heterostructure film and the corresponding 3D periodic bulk structure are compared. The results find such a heterostructure to be stable and possess p-type semiconducting characteristics. Due to the heterostructure’s weak interlayer bonding, its carrier mobility is essentially governed by the constituent layers; the hole mobility is governed by the PbS bilayer, whereas the electron mobility is governed by the MoS2 monolayer. Furthermore, we estimate the hole mobility to be relatively high (~106 cm2V−1s−1), which can be useful for ultra-fast devices at the nanoscale.

Highlights

Principles Study of a MoS2 -PbS vanTwo-dimensional (2D) materials are celebrated among the scientific community, due to the unparalleled exquisite properties compared to their bulk counterparts, arising from the quantum confinement effects
Occurring van der Waals (vdW) structures such as cylindrite and franckeite belong to a family of complex, misfit, layered sulfide minerals
Merelaniite is bulk composed predominantly here focus on heterostructures that are inspired by, but simplified of a stacking of a MoS2-based monolayer (H) incommensurately aligned with a PbS-based from another naturally occurring cylindrite group, the relatively newly bilayer (Q) [24]

Summary

Introduction

Two-dimensional (2D) materials are celebrated among the scientific community, due to the unparalleled exquisite properties compared to their bulk counterparts, arising from the quantum confinement effects. Occurring vdW structures such as cylindrite and franckeite belong to a family of complex, misfit, layered sulfide minerals. Merelaniite is bulk composed predominantly here focus on heterostructures that are inspired by, but simplified of a stacking of a MoS2-based monolayer (H) incommensurately aligned with a PbS-based from another naturally occurring cylindrite group, the relatively newly bilayer (Q) [24]. We investigated the stability and electronic properties of this 2D vdW heterostructure plane of molybdenite (MoS2) mineral was recently reported, thereby suggesting the existemploying density functional theory. The formation of such layered PbS precipitates along ence of MoS.

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