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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
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Self-assembly of catalytically active colloidal molecules: tailoring activity through surface chemistry
Rodrigo Soto1, Ramin Golestanian2
1Departamento de Física, Facultad de Ciencias Físicas y Matemáticas Universidad de Chile, Avenida Blanco Encalada 2008, Santiago, Chile and Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP, United Kingdom.
Physical Review Letters
|March 4, 2014
Summary
Catalytically active colloids form self-assembled molecules in a nonequilibrium system. These molecules exhibit tunable activity, including movement and spin, based on their properties and environment.
Area of Science:
- Colloid science
- Chemical physics
- Soft matter physics
Background:
- Ionic systems exhibit equilibrium properties with action-reaction symmetry.
- Nonequilibrium systems offer novel physical phenomena beyond equilibrium constraints.
Purpose of the Study:
- To investigate a nonequilibrium analogue of ionic systems using catalytically active colloids.
- To explore the self-assembly and emergent properties of these colloidal suspensions.
Main Methods:
- Studying heterogeneous and dilute suspensions of catalytically active colloids.
- Analyzing the formation of self-assembled colloidal molecules.
- Investigating the activity (translational velocity and spin) of these molecules.
Main Results:
- Symmetrically coated colloids self-assemble into molecules.
- These molecules can be inert or exhibit spontaneous activity (net translational velocity and spin).
- Activity is dependent on molecular symmetry, constituents, surface chemistry, and ambient variables.
Conclusions:
- Catalytically active colloids provide a model for studying action-reaction symmetry breaking in nonequilibrium systems.
- Self-assembled colloidal molecules exhibit tunable dynamic properties.
- Surface chemistry and environmental factors control the emergent activity of these colloidal assemblies.
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