Subjected to the bias voltage and the tunneling current in the scanning tunneling microscope,freestanding graphene membranes undergo a special mirror buckling phenomenon,which has not yet been systematically investigated.In order to investigate the effect of cross-section,semi-elliptical cross-section graphene membranes models based on coarse-grained molecular dynamics were used to analyze the mirror buckling behavior in combination with experiments.The results show that the semi-elliptic cross-section graphene membrane is capable of allowing deformation with positive and negative curvature changes,without mirror buckling.The deformation of the graphene membrane in the case of large depth-span ratio is found to be insensitive to the effect of temperature.Comparison of the calculated results in this paper with those of fan-shaped cross-section graphene membrane in the literature shows that the fan-shaped cross-section is more prone to mirror buckling.The reason is related to the initial structure.The semi-ellipsoidal cross-section shows smaller deformation due to the smaller curvature of its end,with the atomic arrangement closer to those of 2D graphene,and smaller position change of the carbon atoms during the process of energy equilibrium due to temperature change.This study on the mechanical characteristics of mirror buckling provides theoretical foundation for the development of energy harvesting devices.
维普
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