A Review of Femtosecond-Laser-Induced Underwater Superoleophobic Surfaces

Underwater superoleophobic surfaces have attracted increasing interest because of their remarkable antioil ability and wide range of promising applications. In the meantime, femtosecond laser microfabrication becomes a rising star in the field of micro/nanomanufacturing based on the advantages of negligible heat-affected zone, no-contact process, precise ablation threshold, and high resolution. The collision of femtosecond laser microfabrication and achieving underwater superoleophobicity finally produces some colorful fireworks. In this review, the recent progress of femtosecond-laser-induced underwater superoleophobic surfaces, mainly including materials, fabrication, properties, multifunctions, and applications, is summarized. The related background is first introduced to show the principle for creating an underwater superoleophobic surface and the unique features of femtosecond laser. Based on the principle of ''from in-air superhydrophilicity to underwater superoleophobicity,'' underwater superoleophobicity is achieved on different kinds of materials surfaces by simple femtosecond laser ablation. Furthermore, the femtosecond-laser-induced underwater superoleophobic surfaces can also be endowed with some additional properties such as controllable oil adhesion, underwater anisotropic oil wettability, good transparency, and durability, leading to the resultant surfaces that have various practical applications. The development of underwater superoleophobicity is still in its ''toddler stage,'' so the existing challenges and future prospects of this growing field are discussed finally.