Real-time Mode-switching of a Self-propelled Droplet Controlled by the Photosensitive Belousov-Zhabotinsky Reaction

Variety of self-propelled droplets have been reported, which originate from interfacial chemical reactions and sometimes show sensitivity to environmental conditions. In this paper, a photosensitive Belousov-Zhabotinsky (BZ) droplet was prepared in an oil phase under illumination whose intensity changed in time. As a result, the droplet motion transited between random and oscillatory motions concurrent with the internal BZ state. The success in the real-time mode-switching reveals that separating the role is one promising strategy to realize desired functionality.