Superlattice Thermal Modulation in MoS2 by Defect Engineering

Abstract

${\mathrm{MoS}}_2$ is one of the most investigated and promising transition-metal dichalcogenides. Its popularity stems from the interesting properties of the monolayer phase, which can serve as the fundamental block for numerous applications. In this paper, an atomistic perspective on the modulation of thermal transport properties in monolayer ${\mathrm{MoS}}_2$ through strategic defect engineering, specifically the introduction of sulfur vacancies is proposed. Using a combination of molecular dynamics simulations and lattice dynamics calculations, how various distributions of sulfur vacancies (ranging from random to periodically arranged configurations) affect its thermal conductivity is shown. Notably, it is observed that certain periodic arrangements restore the thermal conductivity of the pristine system, due to a minimized interaction between acoustic and optical phonons facilitated by the imposed superperiodicity. This research deepens the understanding of phononic heat transport in two-dimensional (2D) materials and introduces a different point-of-view for phonon engineering in nanoscale devices, offering a pathway to enhance device performance and longevity through tailored thermal management strategies.