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This content will become publicly available on June 8, 2024

Title: Active Colloids as Models, Materials, and Machines

Active colloids use energy input at the particle level to propel persistent motion and direct dynamic assemblies. We consider three types of colloids animated by chemical reactions, time-varying magnetic fields, and electric currents. For each type, we review the basic propulsion mechanisms at the particle level and discuss their consequences for collective behaviors in particle ensembles. These microscopic systems provide useful experimental models of nonequilibrium many-body physics in which dissipative currents break time-reversal symmetry. Freed from the constraints of thermodynamic equilibrium, active colloids assemble to form materials that move, reconfigure, heal, and adapt. Colloidal machines based on engineered particles and their assemblies provide a basis for mobile robots with increasing levels of autonomy. This review provides a conceptual framework for understanding and applying active colloids to create material systems that mimic the functions of living matter. We highlight opportunities for chemical engineers to contribute to this growing field.

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Award ID(s):
2038305 2141112
NSF-PAR ID:
10480188
Author(s) / Creator(s):
; ;
Publisher / Repository:
Annual Reviews
Date Published:
Journal Name:
Annual Review of Chemical and Biomolecular Engineering
Volume:
14
Issue:
1
ISSN:
1947-5438
Page Range / eLocation ID:
1 to 30
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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