Natural triterpenoid-tailored self-assembled chiral helical ribbons for regulating droplet bounce

The inhibition of droplet bounce on solid interfaces is of great importance in many fields, particularly in pesticide spraying, as undesired rebound often causes pesticide waste and weakens its performance. Here, we synthesize a natural triterpenoid-derived amphiphile that can self-assemble into chiral helical ribbons in a cooperative nuclear-elongation manner, with a realization of chirality transfer and amplification from molecular to supramolecular level. These helical ribbons are able to inhibit droplet rebound on a hydrophobic surface regardless of whether the inclined angle of substrate is 0°, 30°, or 60°. The physical entanglements between helical ribbons and the rough micro-/nanostructures of the surface are proposed to be responsible for this inhibition and the consumption of impact kinetic energy. Benefiting from such entanglements, droplets were able to deposit on plant leaves, i.e., rice leaf and leek leaf, in a real environment. This work introduces an alternative strategy using supramolecular assemblies as additives to inhibit droplet bounce.