بابک عبازاده

With advances in nanotechnology, two-dimensional nanostructures have shown great promise for a wide range of applications. Of particular interest is their spiral forms as essential components of nanoelectromechanical systems. In this paper, the mechanical behavior of the spirals made of different graphyne structures under tension is investigated using molecular dynamics simulation and the results are compared with graphene nano-spirals. Inspired from the conventional macroscale springs with various cross-sections that have different behaviors against the external axial loads, we comprehensively analyze the effects of various base structures on superelastic deformation capabilities and fracture mechanisms of the nano-spirals. In general, five distinct deformation stages corresponding to van der Waals nonbonding interaction and covalent bonding are observed in the force-strain diagrams. Moreover, the effects of inner and outer radii on the mechanical characteristics are examined. It is found that the stretchability of nano-spirals increases up to a maximum threshold as the outer radius increases, then decreases with its further increase. This decrease is seen more clearly in spirals made of graphene and γ-graphyne while α- and β-graphyne nano-spirals outperform in larger widths. Hence, we show that deliberate manipulation of the base structures can significantly extend the applicability of nano-spirals to larger widths.