Functional fluorination agents for opposite extreme wettability coatings with robustness, water splash inhibition, and controllable oil transport

Abstract

Extreme wettability coatings with repellent-liquids have attracted considerable attention due to their various advantages. Such coatings are not only restricted by poor robustness, but it is difficult to achieve for controlled liquid transport and inhibiting liquid splash due to allowing the droplet to roll-off and bounce, limiting functional applications. Here, we developed two opposite extreme wettability coaitngs with a superhydrophobic-oleophilic coating (SC) and coexisting superoleophobic-superhydrophilic coating (CSC), by changing only the type of fluorination agent. These coatings have shown strong mechanical robustness under sandpaper abrasion, washing, finger-wipe, knife-scratch, and tape-peel due to the synergistic enhancement between native rosin and grafted nanoparticles. Surprisingly, the perfluorinated liquid-infused SC surface could achieve a smart interface for inhibiting splash and recovery of water droplets along with the five-pointed star/branch pattern. Besides, oil droplets could be transported controllable along the desired sinusoidal shape and letter “YOU” wetted path on the water-infused CSC surface by dynamic control. Undoubtedly, these can have a broad applicability spectrum in the micro-fluidics and precision industry.