Adsorption-desorption processes of polydisperse mixtures on a triangular lattice
D Dujak1, I Lončarević2, Lj Budinski-Petković2
1Faculty of Metallurgy and Materials, University of Zenica, Bosnia and Herzegovina.
Summary
Numerical simulations reveal that adding more components or increasing desorption probability reduces equilibrium coverage in polydisperse mixtures. A formula predicts mixture coverage from pure component data.
Area of Science:
- Physics
- Chemistry
- Materials Science
Background:
- Adsorption-desorption processes are crucial in various scientific fields.
- Understanding polydisperse mixtures is complex due to component variability.
Purpose of the Study:
- To investigate adsorption-desorption kinetics of polydisperse mixtures on a triangular lattice.
- To determine how mixture composition and shape properties affect deposition.
- To model the time evolution of coverage and equilibrium states.
Main Methods:
- Numerical simulations were employed to model the system.
- Polydisperse mixtures with varying segment numbers and rotational symmetries were simulated.
- The Mittag-Leffler function was used to describe the time evolution of coverage.
Main Results:
- Equilibrium coverage decreases with an increasing number of mixture components.
- Higher desorption probabilities lead to lower equilibrium coverage, following stretched exponential laws.
- A predictive formula for steady-state coverage was proposed for mixtures of equal-sized objects.
Conclusions:
- The study provides insights into the behavior of complex mixtures during adsorption-desorption.
- The findings offer a method to predict mixture coverage based on individual component properties.
- The Mittag-Leffler function effectively models the observed kinetics.
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