Fabrication of superhydrophobic stainless-steel mesh for oil-water separation by jet electrodeposition

A method for fabricating superhydrophobic stainless-steel meshes based on magnetic field-assisted jet electrodeposition is proposed. Ferromagnetic nickel particles (Nip) were added to the electroplating solution to prepare Ni/Nip coatings with mountain-like rough structure on stainless-steel meshes, followed by application of a parallel magnetic field in the cathode region. Magnetic fields play an indispensable role in the preparation of coatings. Exposure to air for 6 days resulted in a spontaneous switch of the coating from superhydrophilicity to superhydrophobicity and exhibited superoleophilicity. X-ray photoelectron spectroscopy revealed that this transition in wettability was related to spontaneous adsorption of hydrocarbons in the air induced by the coating. Based on the superhydrophobicity and superoleophilicity of the as-prepared Ni/Nip-coated meshes, high-efficiency, high-throughput, and high-purity separation of oil-water mixtures was achieved with a 300-mesh mesh. Furthermore, the as-prepared meshes continue to exhibit a separation efficiency greater than 97.0% and stable reusability even after 50 repeated separations.