Thermal and mechanical characterization of nanoporous two-dimensional MoS₂ membranes

For practical application, determining the thermal and mechanical characterization of nanoporous two-dimensional MoS₂ membranes is critical. To understand the influences of the temperature and porosity on the mechanical properties of single-layer MoS₂ membrane, uniaxial and biaxial tensions were conducted using molecular dynamics simulations. It was found that Young's modulus, ultimate strength, and fracture strain reduce with the temperature increases. At the same time, porosity effects were found to cause a decrease in the ultimate strength, fracture strain, and Young's modulus of MoS₂ membranes. Because the pore exists, the most considerable stresses will be concentrated around the pore site throughout uniaxial and biaxial tensile tests, increasing the possibility of fracture compared to tensing the pristine membrane. Moreover, this article investigates the impacts of temperature, porosity, and length size on the thermal conductivity of MoS₂ membrane using the non-equilibrium molecular dynamics (NEMD) method. The results show that the thermal conductivity of the MoS₂ membrane is strongly dependent on the temperature, porosity, and length size. Specifically, the thermal conductivity decreases as the temperature increases, and the thermal conductivity reduces as the porosity density increases. Interestingly, the thermal and mechanical properties of the pristine MoS₂ membrane are similar in armchair and zigzag directions.