Theoretical modeling of catalytic self-propulsion

Tatiana V. Nizkaya; Evgeny S. Asmolov; Olga I. Vinogradova

doi:10.1016/j.cocis.2022.101637

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arXiv · 2205.14357

Theoretical modeling of catalytic self-propulsion

Tatiana V. Nizkaya·Evgeny S. Asmolov·Olga I. Vinogradova

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Abstract

Self-propelling particles or microswimmers have opened a new field of investigation with both fundamental and practical perspectives. They represent very convenient model objects for experimental studies of active matter, and have implications in nano-robotics, drug delivery, and more. Here, we summarize recent advances in theoretical description of the self-propulsion of catalytic microswimmers that non-uniformly release ions, including its physical origins and the current switch in focus to non-linear effects, geometric tuning and more. In particular, we show that the ionic self-propulsion always includes both diffusiophoretic and electrophoretic contributions, and that non-linear effects are physical causes of a number of intriguing phenomena, such as the reverse in the direction of the particle motion in response to variations of the salt concentration or self-propulsion of electro-neutral particles. We finally suggest several remaining theoretical challenges in the field.

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Tatiana V. Nizkaya, Evgeny S. Asmolov, Olga I. Vinogradova. 2022-05-28. Theoretical modeling of catalytic self-propulsion. https://doi.org/10.1016/j.cocis.2022.101637

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