Opto-Ion-Exchange Enabled Active Swarming System

Swarming behavior often enables systems to achieve intelligent responses that surpass the capabilities of individual components, allowing for complex tasks to be accomplished. Despite significant advances in active swarm research, achieving precise control over swarm responsiveness remains a challenge. In this study, a light-controlled chemical communication-mediated swarming system through integrating the ion-exchange and light decomposition reactions to emulate predator-prey interactions is designed. In this system, ion exchange resin particles (acting as "predators") actively approach and aggregate silver phosphate (Ag₃PO₄) nanoparticles (acting as "prey"), which in turn exhibit light-triggered escape responses driven by photodecomposition-induced ionic gradients. These swarms exhibit a range of novel, light-modulated dynamic behaviors, including enhanced motility, reversible aggregation, repulsion, and distinct reactive states. These behaviors provide valuable insights into active swarm dynamics. Furthermore, the synergistic effects of the collective swarming, active interactions, and light-induced Ag⁺ production establish a robust antibacterial platform capable of rapid and efficient bacterial eradication. This intelligent swarm design presents new possibilities for the development of multifunctional, responsive swarms, offering valuable applications in environmental treatment and beyond.