Self-Propulsion of Chemically Active Droplets

Microscopic active droplets are able to swim autonomously in viscous flows. This puzzling feature stems from solute exchanges with the surrounding fluid via surface reactions or their spontaneous solubilization and interfacial flows resulting these solutes’ gradients. Contrary asymmetric colloids, isotropic spontaneously by exploiting nonlinear coupling of transport self-generated Marangoni flows; such is also responsible for secondary transitions more complex individual collective dynamics. Thanks simple design sensitivity physico-chemical signals, fascinating physicists, chemists, biologists, dynamicists alike analyzing self-propulsion dynamics active-matter systems, developing synthetic cellular models, performing targeted biomedical engineering applications. I review here most recent significant developments this rapidly growing field, focusing on mathematical physical modeling intriguing droplets, together experimental characterization.