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Updated: Apr 5, 2026

Preparation and 3D Tracking of Catalytic Swimming Devices
Published on: July 1, 2016
Enhanced active motion of Janus colloids at the water surface
Xiaolu Wang1, Martin In, Christophe Blanc
1Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-University of Montpellier, Montpellier F-34095, France. Antonio.Stocco@umontpellier.fr.
Abstract:
We have investigated the active motion of self-propelled colloids confined at the air-water interface and explored the possibility of enhancing the directional motion of self-propelled Janus colloids by slowing down their rotational diffusion. The two dimensional motion of micron-sized silica-platinum Janus colloids has been experimentally measured by particle tracking video-microscopy at increasing concentrations of the catalytic fuel, i.e. H2O2. Compared to the motion in the bulk, a dramatic enhancement of both the persistence length of trajectories and the speed has been observed. The interplay of colloid self-propulsion, due to an asymmetric catalytic reaction occurring on the colloid, surface properties and interfacial frictions controls the enhancement of the directional movement. The slowing down of the rotational diffusion at the interface, also measured experimentally, plays a pivotal role in the control and enhancement of active motion.
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