Depletion driven adsorption of colloidal rods onto a hard wall

TL;DR

This paper investigates how colloidal rods adsorb onto a hard wall due to depletion forces, showing that longer rods exhibit significantly stronger adsorption than spheres, based on theoretical and numerical analyses.

Contribution

It provides a detailed analysis of depletion-driven adsorption of rods onto walls, highlighting the dependence on rod length and offering both exact and approximate theoretical insights.

Findings

Long rods exhibit stronger adsorption than spheres.

Depletion forces drive the adsorption process.

Theoretical and numerical methods agree on the results.

Abstract

In a mixed suspension of rods and small polymer coils, the rods adsorb onto a hard wall in contact with the suspension. This adsorption is studied in the low density of rods limit. It is driven by depletion forces and is much stronger for long rods than for spheres. This is shown by means of exact, numerical, calculations and an approximate theory.