Superhydrophobic surfaces have received lots of attention due to their diverse properties, including self-cleaning, corrosion resistance, anti-icing, etc. Superhydrophobic coatings as a surface modification method for the copper substrate can expand many industrial applications such as electronics and aerospace. Owing to their notable corrosion resistance, advantageous mechanical characteristics, and the potential for hierarchical expansion on a copper substrate, nickel and cobalt emerge as viable choices for the development of superhydrophobic coatings. In this work, a rapid and one-step electrodeposition process was used to fabricate superhydrophobic nickel and cobalt coatings with a hierarchical structure from meristic baths on copper substrates. For nickel coating, different surfaces with mushroom-like structures were obtained by adjusting the deposition voltage. The nickel coating obtained at 35 V showed higher hydrophobicity and better corrosion resistance due to the uniform distribution and more appropriate density of the resulting clusters in the surface structure, which provides more trapped air compared to other voltages. According to the obtained results, the nickel coating has achieved a higher contact angle (172.3°) than the cobalt coating (155.6°). Indeed, it delays the complete freezing of the water drop on the surface 6 min more than the cobalt coating. The surface energy of both coatings was so low that the coatings had acceptable oleophobicity. According to the results of electrochemical impedance, very high charge-transfer resistances of 2370 and 756 kΩ.cm2 were obtained for nickel and cobalt coatings, respectively, after relaxation in 3.5 wt.% NaCl solution. After 16 days of immersion in the aggressive solution, high contact angles of 128.7° and 96.8° were obtained for nickel and cobalt coatings, respectively. The stability of nickel and cobalt superhydrophobic coatings in the ambient atmosphere was eva‎luated for 5 months. The contact angles were decreased by 3 % for nickel and 4 % for cobalt coating per month. Although the wetting properties of the cobalt coating were weaker than the nickel coating, it showed better self-cleaning properties where 1/3 numbers of water droplets were enough to clean the droplet pathways from alumina particles.

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