A novel superhydrophobic Ni/Nip coating fabricated by magnetic field induced selective scanning electrodeposition

A new method for preparing superhydrophobic nickel coating by magnetic field induced selective scanning electrodeposition based on additive manufacturing is proposed in this paper in which ferromagnetic nano-nickel particles (Nip) are added to the plating solution and the adsorption regulation of Nip achieve by changing the presence of the magnetic field. Adjusting the magnetic field strength can change the density of the coating micro-nano hierarchical structure, thereby affecting the hydrophobicity. The forming mechanism is mainly divided into four steps: pre-coating, loose adsorption, strong adsorption, and hierarchical structure formation. The surface roughness of the superhydrophobic coating reaches 17.584 μm. The pristine coating spontaneously changed from hydrophilic to superhydrophobic after being exposing to air for 5 days (CA = 155.4°). X-ray photoelectron spectroscopy analysis shows that this phenomenon is due to the oxidation of the coating to produce NiO and adsorbing a large amount of hydrocarbons. At the same time, the electrochemical test result shows that the superhydrophobic coating has great corrosion resistance.