Molecular dynamic study of the mechanical properties of two-dimensional titanium carbides Ti_<i>n</i>+1C_<i>n</i> (MXenes)

Abstract

Two-dimensional materials beyond graphene are attracting much attention. Recently discovered 2D carbides and nitrides (MXenes) have shown very attractive electrical and electrochemical properties, but their mechanical properties have not been characterized yet. There are neither experimental measurements reported in the literature nor predictions of strength or fracture modes for single-layer MXenes. The mechanical properties of two-dimensional titanium carbides were investigated in this study using classical molecular dynamics. Young's modulus was calculated from the linear part of strain-stress curves obtained under tensile deformation of the samples. Strain-rate effects were observed for all Tin+1Cn samples. From the radial distribution function, it is found that the structure of the simulated samples is preserved during the deformation process. Calculated values of the elastic constants are in good agreement with published DFT data.