Depletion-induced percolation in networks of nanorods

TL;DR

This study uses Monte Carlo simulations to explore how depletion forces influence network formation in suspensions of nanorods, revealing a significant decrease in percolation threshold and structural changes driven by anisotropic depletion effects.

Contribution

It provides new insights into how depletion forces affect percolation and structure in rod suspensions, highlighting the role of aspect ratio and anisotropic interactions.

Findings

Depletion forces lower the percolation threshold of nanorods.

The effect increases with the aspect ratio of the rods.

Structural changes are characterized in detail.

Abstract

Above a certain density threshold, suspensions of rod-like colloidal particles form system-spanning networks. Using Monte Carlo simulations, we investigate how the depletion forces caused by spherical particles affect these networks in isotropic suspensions of rods. Although the depletion forces are strongly anisotropic and favor alignment of the rods, the percolation threshold of the rods decreases significantly. The relative size of the effect increases with the aspect ratio of the rods. The structural changes induced in the suspension by the depletant are characterized in detail and the system is compared to an ideal fluid of freely interpenetrable rods.