Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5467660 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2017 | 5 Pages |
Abstract
Irradiation with low energy Ar ions of graphene membranes gives rise to changes in the mechanical properties of this material. These changes have been associated to the production of defects, mostly isolated vacancies. However, the initial state of the graphene membrane can also affect its mechanical response. Using molecular dynamics simulations we have studied defect production in graphene membranes irradiated with 140Â eV Ar ions up to a dose of 0.075Â ÃÂ 1014Â ions/cm2 and different initial strains, from â0.25% (compressive strain) to 0.25% (tensile strain). For all strains, the number of defects increases linearly with dose with a defect production of about 80% (80 defects every 100Â ions). Defects are mostly single vacancies and di-vacancies, although some higher order clusters are also observed. Two different types of di-vacancies have been identified, the most common one being two vacancies at first nearest neighbours distance. Differences in the total number of defects with the applied strain are observed which is related to the production of a higher number of di-vacancies under compressive strain compared to tensile strain. We attribute this effect to the larger out-of-plane deformations of compressed samples that could favor the production of defects in closer proximity to others.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
J. Martinez-Asencio, C.J. Ruestes, E. Bringa, M.J. Caturla,