Equilibrium Adsorption of Hard Disks on Patterned Adhesive Surfaces: A Monte Carlo Simulation Study

TL;DR

This study uses Monte Carlo simulations to analyze how the size, pattern, and arrangement of adhesive regions on surfaces influence the equilibrium adsorption behavior of hard disk particles, revealing key factors for optimizing surface design.

Contribution

It demonstrates how surface pattern geometry and domain size significantly affect particle adsorption, providing insights for designing functional surfaces and biosensors.

Findings

Adsorption is maximized when particle and domain sizes are equal.

Surface pattern geometry influences adsorption efficiency at intermediate chemical potentials.

Steric effects at high coverage weaken the impact of surface patterning.

Abstract

Equilibrium adsorption of disk-like particles on patterned adhesive surfaces is studied using Monte Carlo simulations. The surface is represented as a two-dimensional plane with circular adhesive domains arranged either regularly or randomly, while the particles are modelled as hard disks. The interaction energy between a particle and the surface is defined by the contact area between the particle and the adhesive domains. It is shown that the adsorption behaviour is controlled not only by the total area of the adhesive regions, but also by the geometry of the surface pattern. In particular, the domain size is found to have a significant effect on the adsorption efficiency. The most pronounced effect is observed when the particle and domain sizes are equal, which leads to enhanced adsorption at intermediate values of the chemical potential. At high values of the chemical potential, however, when the particle surface coverage increases, steric effects become important, which weakens the influence of the surface pattern geometry. The obtained results demonstrate that the adsorption efficiency and surface organization of particles can be tuned by choosing the size, coverage, and spatial arrangement of adhesive domains. This study may be useful in the design of functional surfaces, selective adsorption platforms, biosensors, and affinity-based cell sorting systems.