Intrinsic Conductivity of Carbon Nanotubes and Graphene Sheets Having a Realistic Geometry

Published

November 23, 2015

Author(s)

Luis Fernando Vargas Lara, Ahmed M. Hassan, Edward J. Garboczi, Jack F. Douglas

Abstract

The addition of carbon nanotubes (CNTs) and graphene sheets (GSs) into polymeric materials such as epoxy resins can greatly enhance the conductivity and alter the electromagnetic response of the resulting nanocomposite material. The extent of these property modifi cations strongly depends on the structural parameters describing the CNTs and GSs, such as their shape and size, as well as their degree of particle dispersion within the polymeric matrix. To model these property modifi cations in the dilute particle regime, we determine the leading transport virial coefficients describing the conductivity of CNT and GS composites using a combination of path-integral and finite-element calculations. This approach allows for the treatment of the general case in which the ratio between the conductivity of the nanoparticles and the polymer matrix is arbitrary so that insulating, semi-conductive and conductive particles can be treated within a uni ed framework. Ensembles of CNTs and GSs in the form of self-avoiding worm-like cylinders and perfectly flat and random sheet polymeric structures are generated by molecular dynamics simulation to model these complex-shaped carbonaceous nanoparticles. We calculate the electric and magnetic polarizability tensors (\alpha_ E, \alpha_ M) since these properties determine the conductivity virial coefficient [\sigma] in the conductive and insulating particle limits and to estimate [\sigma] in the general case in which the conductivity contrast between the nanoparticle and the polymer matrix is arbitrary. Finally, we propose approximate relationships for \alpha_E and \alpha_M that should be useful in materials design and characterization applications.

Citation

Journal of Chemical Physics

Pub Type

Journals

Keywords

carbon nanotube, graphene, conductivity, polarizability

Citation

, L. , Hassan, A. , Garboczi, E. and Douglas, J. (2015), Intrinsic Conductivity of Carbon Nanotubes and Graphene Sheets Having a Realistic Geometry, Journal of Chemical Physics (Accessed April 25, 2024)