Surface modification to fabricate dual superlyophobic mesh for efficient oil/water separation

How to solve water pollution caused by oil spills using special wetting materials with high efficiency is still a challenge. Herein, dual superlyophobic stainless steel mesh with hierarchical structures was produced via in-situ surface modification. Field emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy elemental (EDX) mapping results show that the frames of the mesh were fully covered by a layer of multi-scale structures. The mesh is both hydrophilic and oleophilic in air, whereas is dual superlyophobic in several kinds of oil-water systems due to its special structures. Artificial polluted waters were prepared using organic oils with diverse density, and then purified via the mesh with separation efficiency >99.90% even after 80 cycles. Moreover, the mesh has stable water penetration ability at various temperature with water flux of similar to to 53.8 L m(-2).s(-1). Water pollutions caused by viscous diesel oil or crude oil were well separated at 65 degrees C with high efficiency (>99.90%), and could also keep this high efficiency at 85 degrees C. Thus, not only a surface modification method is improved to fabricate dual superlyophobic materials, but also a superlyophobic mesh is produced to resolve oil pollution resulted from oil spills. (C) 2020 Elsevier Ltd. All rights reserved.