ABSTRACT
A comparative study regarding the behavior of graphene, porous graphene and graphenylene monolayers under high energy impact is reported. Our results were obtained using a computational model constructed to perform investigations of the dynamics of high velocity fullerenes colliding with free standing sheets of those materials. We employed fully reactive molecular dynamics simulations in which the interatomic interactions were described using ReaxFF force field. During the simulations, free standing monolayers of the investigated materials were submitted to collision with a C60 fullerene molecule at impact angles within the range 0°≤θ≤75°. We considered kinetic energies in the range 0eV≤Ek≤1500eV, that corresponds to a projectile velocity v in the range 0Å/fs≤v≤0.2Å/fs. Also, the failure dynamics of each one of the 2-dimensional materials is described in a comparative analysis in which relevant differences and unique features observed in the mechanical stress dissipation processes are highlighted. Finally, performing hundreds of simulations we were able to map many possible scenarios for these collisions and to construct diagrams that elucidate, for each one of the materials, the possible behaviors under the action of a highly energetic C60 projectile as a function of energy and incident angle.
Subject(s)
Fullerenes , Graphite , Molecular Dynamics Simulation , PorosityABSTRACT
This article contains data on nanoporous carbon materials coming from lignocellulosic components. Such data is directly related to the research paper "Insights into the design of carbon electrodes coming from lignocellulosic components pyrolysis with potential application in energy storage devices: A combined in silico and experimental study" [1]. In this work, the geometrical parameters of nanoporous carbon systems were found with Molecular Dynamics (MD) simulations at the ReaxFF level. The tridimensional structures of such carbon systems are given in Cartesian coordinates. They were computed at different heating rates, simulating the conditions observed in pyrolysis processes of Agave angustifolia leaves, which were carried out in a solar furnace. Nanoporous carbon systems are characterized with radial distribution functions (RDF) and ring distribution profiles.
ABSTRACT
Energetic materials, such as explosives, propellants, and pyrotechnics, are widely used in civilian and military applications. Nanoscale explosives represent a special group because of the high density of energetic covalent bonds. The reactive molecular dynamics (ReaxFF) study of nitrofullerene decomposition reported here provides a detailed chemical mechanism of explosion of a nanoscale carbon material. Upon initial heating, C60(NO2)12 disintegrates, increasing temperature and pressure by thousands of Kelvins and bars within tens of picoseconds. The explosion starts with NO2 group isomerization into C-O-N-O, followed by emission of NO molecules and formation of CO groups on the buckyball surface. NO oxidizes into NO2, and C60 falls apart, liberating CO2. At the highest temperatures, CO2 gives rise to diatomic carbon. The study shows that the initiation temperature and released energy depend strongly on the chemical composition and density of the material.