Vibrational analysis of graphene mass sensor via molecular dynamics simulation

Graphene is one of the youngest member of the nano-carbon material with two-dimensional structure which has extraordinary mechanical and electrical properties. Graphene sheets can also be used as mass sensors. In this paper, the special applications of this substance as a mass sensor are considered. The vibrational behavior of a graphene mass sensor is studied by molecular dynamics simulation method. Also, the effects of increase the dimensions of the rectangular sheet in two zigzag and armchair directions has been studied on natural frequencies. For this purpose, a square graphene sheet has been created in the molecular dynamic environment and the particle displacement is obtained from the molecular dynamics method. The displacements are analyzed using the frequency domain decomposition method and the first natural frequency of the sheet is calculated. Then, the dimensions of graphene sheet have been changed in the zigzag and armchair directions, and the natural frequency of the sheet is also estimated. In order to validate the method, the estimated natural frequency is compared with the results of one of the improved theories of continuous mechanics. In the following, the ability of graphene sheet for detection of attached mass has been examined using the presence of concentrated gold particles. Finally, the sensitivity of graphene sheet to the attached masses is presented.