2021/09/14 by Júnior, M. L. Pereira, da Cunha, W. F., Júnior, R. T. de Sousa +3
#00-xx #FOS: Physical sciences #I.6 #J.2 #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2109.06834
Carbon nano-onions (CNO) are multi-shell fullerenes. In the present work, we used fully atomistic reactive (ReaxFF) molecular dynamics simulations to study the dynamics and structural transformations of CNO structures under high-velocity impacts against a fixed and rigid substrate. We considered single and multi-shell CNO (up to six shells) and at different impact velocities (from 2 up to 7 Km/s). Our results indicated three regimes formed after the CNO impact: slightly deformed CNO (quasi-elastic collision, below 2.0 Km/s), collapsed CNO (inelastic collisions, between 3.0 and 5.0 Km/s) forming a diamondoid-like core, and fragmented CNO yielding linear atomic carbon chains (above 5.0 Km/s). We also discussed the dynamical reconfiguration of carbon-carbon bonds during the collision process. The impact of CNO against the substrate yielded sp3-like bond types for all the used initial velocities. At intermediate velocities (between 3.0 and 5.0 Km/s), the inelastic collision forms diamondoid-like cores by converting a substantial quantity of sp2 bonds into sp3 ones. In the high velocities regime, the total number of sp1, sp2, and sp3 bonds tend to be similar.