About this Abstract |
Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Presentation Title |
Structure-Density-Mechanical Properties of Amorphous Carbon Investigation using ReaxFF Molecular Dynamics |
Author(s) |
Małgorzata Kowalik, Andrei Dernov, Adri van Duin, Traian Dumitrica |
On-Site Speaker (Planned) |
Traian Dumitrica |
Abstract Scope |
Amorphous (a) carbon commonly coats the surfaces of bundles of carbon nanotubes (CNTs) and fills the gaps between these bundles in aerogels synthesized through floating catalyst chemical vapor deposition. The disordered atomic arrangement confers unique properties, which distinguishes a-carbon from the highly-crystalline sp2 structure of CNTs. While force field based molecular dynamics (MD) can predict the mechanics of CNT bundles [1], describing the covalent bonding in a-carbon still presents challenges for the classical interatomic potentials, particularly with capturing the mix of sp2 and sp3 C-C bonding.
In this talk, we discuss a-carbon generated by reactive MD simulated annealing with the use of the ReaxFF Kowalik parameter set [2], and focus on their structure-density-mechanical property relations. We process a large collection of generated network structures for properties (such as density and Young’s moduli) and microscopic measures (such as sp2/sp3 bonding ratio, short-range pair correlation, and distribution of ring sizes comprising covalently bonded atoms), and then benchmark its quality against available experimental data. We discuss the impact of the annealing time on the degree of graphitization, dependence on the annealing temperature and the density of the given a-carbon structures. Screening the collection of a-carbons uncovers correlations between the mechanical properties and the microscopic structural measures. We found that ReaxFF based MD approach emerges as a viable approach for generating and analyzing mechanical properties of a-carbon.
[1] H Xu et al. ACS Appl. Nano Mater. 4, 11115 (2022).
[2] M. Kowalik et al. J. Phys. Chem. B 123, 5357 (2019). |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |