Simulations of Graphene Sheets Based on the Finite Element Method and Density Functional Theory: Comparison of the Geometry Modeling under the Influence of Defects

In the present research, imperfect graphene sheets were generated and their vibrational property was studied via finite element analysis. The effect of vacant sites in the arrangement of these nano-structures was examined. The fundamental frequency of the defect free and imperfect nano-sheets was acquired based on two different approaches. The first approach was a pure finite element simulation. The second approach for comparison purpose was a recently reported refined finite element simulation at which the vicinity of a defect was first evaluated according to the density functional theory (DFT) and then the refined geometry was implemented into a finite element model. The findings of this research show that the fundamental frequency of graphene sheets decreases by presenting microscopic imperfection to the formation of these nano-materials. In addition, it was pointed out that the geometry based on the more precise DFT simulations gives a higher decrease in the fundamental frequency of the sheets for all considered cases.Griffith Sciences, Griffith School of EngineeringFull Tex