English

Self-solidifying active droplets showing memory-induced chirality

Soft Condensed Matter 2023-10-25 v2 Materials Science Fluid Dynamics

Abstract

Most synthetic microswimmers do not reach the autonomy of their biological counterparts in terms of energy supply and diversity of motion. Here we report the first all-aqueous droplet swimmer powered by self-generated polyelectrolyte gradients, which shows memory-induced chirality while self-solidifying. An aqueous solution of surface tension-lowering polyelectrolytes self-solidifies on the surface of acidic water, during which polyelectrolytes are gradually emitted into the surrounding water and induce linear self-propulsion via spontaneous symmetry breaking. The low diffusion coefficient of the polyelectrolytes leads to long-lived chemical trails which cause memory effects that drive a transition from linear to chiral motion without requiring any imposed symmetry breaking. The droplet swimmer is capable of highly efficient removal (up to 85%) of uranium from aqueous solutions within 90 min, benefiting from self-propulsion and flow-induced mixing. Our results provide a route to fueling self-propelled agents which can autonomously perform chiral motion and collect toxins.

Keywords

Cite

@article{arxiv.2302.04195,
  title  = {Self-solidifying active droplets showing memory-induced chirality},
  author = {Kai Feng and José Carlos Ureña Marcos and Aritra K. Mukhopadhyay and Ran Niu and Qiang Zhao and Jinping Qu and Benno Liebchen},
  journal= {arXiv preprint arXiv:2302.04195},
  year   = {2023}
}
R2 v1 2026-06-28T08:35:14.961Z