Carbon Nanoscrolls at High Impacts: A Molecular Dynamics Investigation

TL;DR

This study uses molecular dynamics simulations to explore how carbon nanoscrolls behave under high-velocity impacts, revealing deformation, unscrolling, and bond formation processes influenced by impact velocity and orientation.

Contribution

It provides the first detailed atomistic analysis of high-impact behavior of carbon nanoscrolls, highlighting key parameters affecting structural transformations.

Findings

Nanoscrolls can undergo large deformations and fractures.

Unscrolling into graphene nanoribbons occurs under certain conditions.

Fused scroll walls form when impacting with open ends at specific velocities.

Abstract

The behavior of nanostructures under high strain-rate conditions has been object of interest in recent years. For instance, recent experimental investigations showed that at high velocity impacts carbon nanotubes can unzip resulting into graphene nanoribbons. Carbon nanoscrolls (CNS) are among the structures whose high impact behavior has not yet been investigated. CNS are graphene membranes rolled up into papyrus-like structures. Their unique open-ended topology leads to properties not found in close-ended structures, such as nanotubes. Here we report a fully atomistic reactive molecular dynamics study on the behavior of CNS colliding at high velocities against solid targets. Our results show that the velocity and scroll axis orientation are key parameters to determine the resulting formed nanostructures after impact. The relative orientation of the scroll open ends and the substrate is also very important. We observed that for appropriate velocities and orientations, the nanoscrolls can experience large structural deformations and large-scale fractures. We have also observed unscrolling (scrolls going back to planar or quasi-planar graphene membranes), unzip resulting into nanoribbons, and significant reconstructions from breaking and/or formation of new chemical bonds. Another interesting result was that if the CNS impact the substrate with their open ends, for certain velocities, fused scroll walls were observed.