The effects of different possible modes of uniaxial strain on the tunability of electronic and band structures in MoS 2 monolayer nanosheet via first-principles density functional theory

Ab-initio density functional theory-based calculations have been performed on monolayer (ML) MoS 2 nanosheet to study the variation of its electronic properties with the application of uniaxial tensile and compressive strain along its two non-equivalent lattice directions, namely, the zig-zag and the arm-chair directions. Among all the strain types considered in this study, uniaxial tensile strain applied along the zig-zag direction is found to be the most efficacious, inducing a greater tunability in the band gap over a large energy range (from 1.689 to 0.772 eV corresponding to 0–9% of applied strain), followed by uniaxial tensile strain along arm-chair direction. In contrast, the ML– MoS 2 nanosheet is found to be less sensitive to the compressive strain applied uniaxially along both the arm-chair as well as zig-zag directions. Moreover, the charges on Mo and S atoms are not found to undergo considerable changes under the application of uniaxial strain, as the atomic motion along the other direction is free from any constraint.