Janus droplet as a catalytic micromotor

Sergey Shklyaev

doi:10.1209/0295-5075/110/54002

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arXiv · 1506.00114

Janus droplet as a catalytic micromotor

Sergey Shklyaev

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Abstract

Self-propulsion of a Janus droplet in a solution of surfactant, which reacts on a half of a drop surface, is studied theoretically. The droplet acts as a catalytic motor creating a concentration gradient, which generates its surface-tension-driven motion; the self-propulsion speed is rather high, $60\; {\rm μm/s}$ and more. This catalytic motor has several advantages over other micromotors: simple manufacturing, easily attained neutral buoyancy. In contrast to a single-fluid droplet, which demonstrates a self-propulsion as a result of symmetry breaking instability, for Janus one no stability threshold exists; hence, the droplet radius can be scaled down to micrometers. The paper was finalized and submitted by Denis S. Goldobin after Sergey Sklyaev had sadly passed away on June 2, 2014.

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Sergey Shklyaev. 2015-05-30. Janus droplet as a catalytic micromotor. https://doi.org/10.1209/0295-5075%2F110%2F54002

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