Femtosecond laser induced robust periodic nanoripple structured mesh for highly efficient oil-water separation

Marine oil spills have induced severe water pollution and threatened sea ecosystems, which also result in a loss of energy resources. To deal with this problem, much work has been done for using superhydrophobic or superhydrophilic mesh for oil-water separation. Nevertheless, there are still great challenges in the rapid fabrication of extremely durable mesh with superwetting properties, particularly considering the highly efficient oil-water separation. In this study, we present a simple, efficient method to fabricate superhydrophilic and underwater superoleophobic stainless steel mesh surfaces with one-step femtosecond laser induced periodic nanoripple structures. The as-prepared mesh shows high separation efficiency, which is higher than 99% for various oil-water mixtures. More importantly, the wettability and the separation efficiency of the fabricated mesh show no obvious change after the abrasion tests and corrosion tests, indicating that the as-prepared samples possess robust stability. This study provides an efficient route for constructing durable and highly efficient separation mesh, which can be applied in the cleanup of large-scale oil spills in the near future.