Simulation of the electrical conductivity of two-dimensional films with aligned rod-like conductive fillers: effect of the filler length dispersity

TL;DR

This study uses Monte Carlo simulations to analyze how the length dispersity and alignment of rod-like fillers affect the electrical conductivity and phase transition in two-dimensional films, revealing critical concentration dependencies and anisotropic effects.

Contribution

It introduces a detailed simulation approach to understand the impact of filler length dispersity and alignment on electrical conductivity in 2D films, highlighting the role of length dispersity in lowering critical concentration.

Findings

Greater length dispersity reduces the critical concentration for conductivity.

Conductivity anisotropy is more pronounced near the phase transition.

Finite size effects are significant only near the phase transition.

Abstract

Using Monte Carlo simulation, we studied the electrical conductivity of two-dimensional films. The films consisted of a poorly conductive host matrix and highly conductive rod-like fillers (rods). The rods were of various lengths fitting a log-normal distribution. They could be aligned along a direction. Special attention was paid to films having completely aligned rods. The impact of length dispersity and the extent of rod alignment on the insulator-to-conductor phase transition was studied. The greater the length dispersity the smaller the critical concentration. The anisotropy of the electrical conductivity was more pronounced in the vicinity of the phase transition. A finite size effect was found to be significant only in the vicinity of the phase transition.