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Published on: May 20, 2014
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Self-Organization of Binary Colloidal Mixtures via Diffusiophoresis
Lijie Lei1,2, Shuo Wang1, Xuemao Zhou1
1Institute for Advanced Study, Shenzhen University, Shenzhen, China.
Frontiers in Chemistry
|April 1, 2022
Summary
Active and passive colloids interact through phoretic forces, forming diverse structures like schools and clusters. Simulations reveal how tuning particle properties influences these dynamic organizations.
Area of Science:
- Colloid science
- Soft matter physics
- Chemical engineering
Background:
- Catalytic colloids exhibit self-propulsion and interact via chemotaxis.
- Phoretic interactions, driven by surface activity and mobility, govern colloid behavior.
Purpose of the Study:
- To simulate and analyze the dynamic structures formed by mixtures of active and passive colloids.
- To investigate the influence of particle properties (surface mobility, size, area fraction) on emergent collective behaviors.
Main Methods:
- Brownian dynamics simulations were employed to model binary mixtures of active and passive colloids.
- Phoretic interactions were defined by surface activity and surface mobility parameters.
Main Results:
- Rich dynamic structures were observed, including schools with exclusion zones, yolk/shell clusters, and stable active-passive alloys.
- Tuning passive colloid size ratio promoted phase separation and yolk/shell structures.
- Increasing active colloid area fraction led to the formation of stable alloys from dynamic clusters.
- Nonreciprocity in phoretic interactions resulted in dynamical cluster formation.
Conclusions:
- Simulated binary active colloid systems display complex nonequilibrium phenomena.
- These phenomena mimic dynamic organizations observed in natural active/passive systems.
- Particle properties significantly control the emergent collective behaviors and phase behavior of colloid mixtures.
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