Underwater superoleophobic copper mesh coated with block nano protrusion hierarchical structure for efficient oil/water separation

Compared with monolayer nanosheet membranes, multilayer nanosheet membranes have low energy consumption and can be mass-produced for industrial applications. Herein, a multi-layer nanostructured membrane, nickel-doped brochantite/Cu(OH)2 nano protrusion structure coated copper meshes (NBCPCMs), were successfully prepared. Firstly, the surface of the copper mesh was etched by chemical oxidation to form a disordered copper hydroxide nanosheet layer. Secondly, the etched copper mesh sur-face was coated with nickel-controlled brochantite block-like protrusions by hydrothermal synthesis method, and nickel-doped brochantite/Cu(OH)2 nanosheets were generated by high pressure. The results showed that NBCPCM-4 had excellent hydrophilic/underwater superoleophobicity, the oil-water separa-tion efficiency of immiscible cyclohexane/water mixture was the highest, about 98.54%, and still had a very high flux (>60 (kL/(h.m2))) after multiple cycles of separation. In addition to ultra-high separation efficiency, NBCPCM-4 also had super durability. The copper mesh maintained good underwater super-oleophobicity in different aqueous solutions. Therefore, NBCPCM-4 is a potential high-efficiency and sus-tainable oil-water separation membrane material. It is expected that the developed technology is useful for sea transportation and marine environment management, along with other industries. (c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.