Kinetics of random sequential adsorption of interacting particles on partially covered surfaces

The random sequential adsorption (RSA) approach was used to analyse adsorption kinetics of charged spheres at charged surfaces precovered with smaller sized, likely charged particles. The algorithm of M. R. Oberholzer et al. [20] was exploited to simulate adsorption allowing electrostatic interaction in three dimensions, that is, particle-particle and particle-surface interactions during the approach of a particle to the substrate. The calculation of interaction energies in the model was achieved with the aid of a many-body superposition approximation. The effective hard particle approximation was used for determination of corresponding simpler systems of particles, namely: the system of hard spheres, the system of particles with perfect sink model of particle-interface interaction, and the system of hard discs at equilibrium. Numerical simulations were performed to determine adsorption kinetics of larger particles for various surface concentration of smaller particles. It was found that in the limit of low surface coverage the numerical results were in a reasonable agreement with the formula stemming from the scaled particle theory with the modifications for the sphere-sphere geometry and electrostatic interaction. The results indicate that large particle-substrate attractive interaction significantly reduces the kinetic barrier to the large, charged particle adsorption at a surface precovered with small, likely charged particles.