Tunneling conductivity in anisotropic nanofibre composites: a percolation-based model

TL;DR

This paper presents a percolation-based model combining the Critical Path Approximation with a lattice approach to analyze tunneling conductivity in anisotropic nanofibre composites, accounting for nanoparticle orientation and clustering effects.

Contribution

It introduces a novel integrated model that incorporates anisotropic tunneling conductance estimates and explores the influence of orientational order on conductivity.

Findings

Conductivity strongly depends on the standard deviation of the orientational order parameter.

The model shows significant effects of nanoparticle orientation and clustering on composite conductivity.

Conductivity varies notably with volume fraction and degree of clustering.

Abstract

The Critical Path Approximation ("CPA") is integrated with a lattice-based approach to percolation to provide a model for conductivity in nanofibre-based composites. Our treatment incorporates a recent estimate for the anisotropy in tunnelingbased conductance as a function of the relative angle between the axes of elongated nanoparticles. The conductivity is examined as a function of the volume fraction, degree of clustering, and of the mean value and standard deviation of the orientational order parameter. Results from our calculations suggest that the conductivity can depend strongly upon the standard deviation in the orientational order parameter even when all the other variables (including the mean value of the order parameter <S>) are held invariant.