Extended random sequential adsorption model of irreversible deposition processes: from simulations to experiments

Area of Science:

• Colloid and Surface Science
• Statistical Physics
• Materials Science

Background:

• Irreversible deposition of colloidal particles is crucial in many scientific and industrial applications.
• Understanding particle behavior during deposition, especially the transition between different deposition regimes, remains a challenge.

Purpose of the Study:

• To present an experimental study on irreversible colloidal particle deposition.
• To introduce and validate a generalized random sequential adsorption model that accounts for particle diffusion during deposition.
• To analyze the transition from random sequential adsorption-like to ballistic-like deposition behavior.

Main Methods:

• Experimental investigation of colloidal particle deposition on a solid surface.
• Analysis of experimental data using a novel generalized random sequential adsorption model.
• Inclusion of particle diffusion during deposition and number of adhesion trials as key parameters in the model.
• Characterization of radial distribution functions and number density fluctuations.

Main Results:

• The generalized model successfully describes the continuous transition between random sequential adsorption and ballistic deposition regimes.
• The model accurately accounts for experimental observations of radial distribution functions and number density fluctuations across various particle sizes and coverages.
• A relationship was found between diffusion parameters and effective particle radius (d(s)/R proportional to R*(-2)).
• An empirical connection between diffusion and adhesion trial parameters was established: (d(s)/R)n(s)(2/3) = C, with C ≈ 50.

Conclusions:

• The developed statistical model provides an accurate description of irreversible deposition processes.
• The model is effective regardless of the relative influence of gravity and diffusion.
• The findings offer a unified framework for understanding colloidal deposition dynamics.