COMPUTATION TO STRUCTURAL AND ELECTRONIC PROPERTIES EVOLUTION OF MONOLAYER MOS2 INDUCED BY STRESS

Based on the first-principles approach of density functional theory, the evolution of the structural and electronic properties of monolayer MoS 2 due to stress is investigated by using the CASTEP module in the Material Studio software, which mainly calculates the changes of the energy band structure of monolayer MoS 2 when it is under different stresses. The calculation results show that: after applying a tensile stress of 1% lattice strain to monolayer MoS 2 , the bottom point of the conduction band in its energy band remains unchanged, but the top point of its valence band will be shifted, so that its energy band structure will be transformed from a direct band gap to an indirect band gap, and with the increase of the stress up to 10%, it still maintains the indirect band gap unchanged but with the consequent decrease of the forbidden band width. On the contrary, when the single-layer MoS 2 is compressed under a compressive stress, when compressed to -10%, the single-layer MoS 2 is transformed from a semiconductor to a metal, and the absorption ability of the light in the layer will be weakened, and the corresponding reflectance will be enhanced to the point of total reflection, which is the characteristic of the metal at this time.