The physical fundamentals of the electrical conductivity in nanotube-based composites

Abstract

In this article, we show that the classical theories of percolation, continuum percolation, and effective medium theory can account for all the features of electrical conductivity dependence on the content of the fibrous filler in composites in which the conducting particles are nanotubes, nanofibers, and nanowires. We show this by applying the corresponding concepts of the percolation nodes–links–blobs model, the excluded volume and the effective local conductance. In particular, in contrast with ad hoc or empirical evaluations of others, our analysis accounts simultaneously and quantitatively for the variety of values of the percolation thresholds, the electrical conductivity exponent, and the conductivity prefactor in all those systems. Our approach, therefore, provides a well-based theoretical physical framework for a comprehensive understanding of the electrical conductivity in those composites.