Facile fabrication of robust superhydrophobic/superoleophlic Cu coated stainless steel mesh for highly efficient oil/water separation

• A novel robust copper film has a characteristic of dense stacking structure accumulated by micrometer stone-like grain, which created a suitable rougher surface. • The copper coated stainless steel mesh show excellent mechanical, chemically stable, excellent self-cleaning, anti-corrosion and oil–water separation efficiency. • The Cu coated mesh possess a water contact angle, a sliding angle and oil contact and has 97.6% oil–water separation efficiency after 40 cycles of separation. A mechanically durable and chemically stable Cu coated stainless steel mesh is successfully prepared adopting a simple electrodeposition method. The novel copper film is featured with characteristics of dense stacking structure accumulated by micrometer stone-like grain, through which a suitable rougher surface is therefore formed, exhibiting excellent performance in mechanical stability, chemical endurance, self-cleaning and oil–water separation efficiency. The influences of the electrodeposition current and time on microstructural evolution, as well as the wettability were discussed. The superhydrophobic and superhyoleophilic coating possesses a water contact angle (WCA) of 160 ± 2°, a sliding angle (SA) of 2.2 ± 0.1° and oil contact angle (OCA) of 0° under the deposition condition of 0.18 A (0.033 A/cm 2 ) for 150 s. The robust films maintain its superhydrophobicity not only in acid and alkali environments, but also after wear test under a pressure of 6.5 kPa with a length of 100 cm. In addition, the proposed film can withstand 2.35 kPa of water intrusion pressure. It exhibit high efficient separation for a mixture of oils or organic solvents with water and could achieve 98.3% separation efficiency in a short time of 9.2 s. The proposed design has great potential and prosperous future in practical industrial applications for mass production and efficient oil–water separation.