Controlled rippling of graphene via irradiation and applied strain modify its mechanical properties: a nanoindentation simulation study

Abstract

Ripples present in free standing graphene have an important influence on the mechanical behavior of this two-dimensional material. In this study, we show through nanoindentation simulations, how out-of-plane displacements can be modified by strain, resulting in softening of the membrane under compression and stiffening under tension. Irradiation also induces changes in the mechanical properties of graphene. Interestingly, compressed samples, irradiated at low doses are stiffened by the irradiation, whereas the samples under tensile strain do not show significant changes in their mechanical properties. These simulations indicate that vacancies produced by the energetic ions cannot be the ones directly responsible for this behavior. However, changes in roughness induced by the momentum transferred from the energetic ions to the membrane, can explain these differences. These results provide an alternative explanation to recent experimental observations of the stiffening of graphene under low dose irradiation, as well as the paths to tailor the mechanical properties of this material via applied strain and irradiation.

Multi‐scale damping of graphene foam‐based polyurethane composites synthesized by electrostatic spraying

“…High damping of PU‐GrF composites can also be attributed to the hollow GrF framework, which allows its wall to act as a membrane exposed to dynamic loading. Using non‐linear Foppl membrane theory , the relationship between the indentation load and displacement is and the expression between the contact stiffness and indentation displacement is deduced from Eq . as. where F ( h ) is the indentation load, h is the indentation displacement, is membrane tension, a is the membrane radius, q is Poisson's ratio, E 2 D is the two‐dimensional Young's modulus and S ( h ) is the contact stiffness.…”

“…High damping of PU-GrF composites can also be attributed to the hollow GrF framework, which allows its wall to act as a membrane exposed to dynamic loading. Using non-linear Foppl membrane theory [64], the relationship between the indentation load and displacement is…”

The direct growth of planar and vertical graphene on Si(100) via microwave plasma chemical vapor deposition: synthesis conditions effects

“…Increased ion irradiation can explain vacancy formation when using plasma power of 1.7 kW, as shown in numerous studies. [57][58][59][60][61][62] Doubling the processing pressure did not inuence the graphene synthesized using a power of 1.7 kW (Fig. S4 †).…”

Evaporation of Water on Suspended Graphene: Suppressing the Effect of Physically Heterogeneous Surfaces

“…The suspended graphene, which is a result of oscillating carbon atoms, can be formed by the distortion of C−C bonds following the work of Caturla et al 64 On the basis of a previous work, 65 we considered two regions with a width of 4 Å at the opposite ends of the graphene substrate. The two regions were held fixed, while the NVT ensemble was applied to the carbon atoms between them.…”