The role of topological defects on the mechanical properties of single-walled carbon nanotubes

ABSTRACT

Carbon nanotubes (CNTs) are among the most employed nanomaterials in developing new technologies. Their applicability requires a fundamental understanding of the chirality and defect effects on the mechanical properties. In this study, molecular dynamics (MD) simulations were performed to investigate the mechanical response of defective single-walled carbon nanotubes (SWCNTs) under tension loading. The Stones-Wales, monovacancy, and the divacancy reconstructions (585, 555777, and 555567777) defects were considered. In addition, we investigated the influence of the adaptive intermolecular reactive bond order (AIREBO) potential cut-off radii on the defect formation energy of SWCNTs. Our results reveal that the tensile strength properties are notably dependent on the chirality and defect configurations at strains over 8%. Energetically favourable defects have a high impact on the mechanical response of SWCNTs. A combination of certain defects may lead the control on the fracture pattern of the SWCNTs, which can significantly contribute to the designing of innovative nanostructures with tailored properties.

KEYWORDS:

• Carbon nanotubes
• defects
• fracture pattern
• molecular modelling
• fracture strength

Acknowledgments

We gratefully acknowledge support of the RCGI – Research Centre for Gas Innovation, hosted by the University of São Paulo (USP) and sponsored by FAPESP – São Paulo Research Foundation (2014/50279-4, 2020/15230-5, and project number 2020/01558-9) and Shell Brasil, and the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation. The authors also acknowledge National Council for Scientific and Technological Development (CNPq) through grant 307064/2019-0 for financial support. The computational time for the calculations was provided by High-Performance Computing facilities at the University of de São Paulo (USP).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

The data is available under direct request to the authors.

Author contributions

Conceptualisation, methodology, MD implementation, investigation, numerical results, writing original draft, editing: DAD. Conceptualisation, methodology and data analysis, supervision, funding author 1, and manuscript editing: CRM. All authors have read and agreed to the manuscript’s published version.

Additional information

Funding

We gratefully acknowledge support of the RCGI – Research Centre for Gas Innovation, hosted by the University of São Paulo (USP) and sponsored by FAPESP – São Paulo Research Foundation (2014/50279-4, 2020/15230-5, and project number 2020/01558-9) and Shell Brasil, and the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation. The authors also acknowledge National Council for Scientific and Technological Development (CNPq) through grant 307064/2019-0 for financial support. The computational time for the calculations was provided by High-Performance Computing facilities at the University of de São Paulo (USP).