Femtosecond laser controlling underwater oil-adhesion of glass surface

This paper presents a simple and effective method to fabricate underwater superoleophobic glass surfaces with extremely controllable oil-adhesion through the femtosecond laser microfabrication. The laser-irradiated surfaces show micro-/nanoscale hierarchical structures and similar underwater superoleophobicity. By adjusting the average distance of laser pulse focus, the oil-adhesion of the as-prepared underwater superoleophobic surfaces can be controlled from ultralow to ultrahigh. This controllability of oil-adhesion is ascribed to the different wetting states for the oil droplet on the surface that results from the change of the morphology and microstructure after femtosecond laser irradiation. The as-prepared superoleophobic surfaces with ultralow oil-adhesion have the anti-oil contamination ability in water. The ultrahigh oil-adhesive superoleophobic surfaces can be used as a mechanical hand'' to transfer small oil droplets without any volume loss in water environment, endowing the controllable oil-adhesive surfaces with important applications in the fusion of oil/organic microdroplets.