The aim of this study is to assess the synergistic effect of two corrosion control strategies: application of an inhibitor and enhancing the surface superhydrophobicity, for protection of electrodeposited nickel in saline solutions. For this purpose, 4-Mercaptopyridine (C5H5NS) was added to the synthetic sea water solution and its corrosion inhibition efficiency was evaluated on electrodeposited smooth bright nickel layer and nickel films with hierarchical micro/nano structure. Stearic acid was used to tune the wetting properties of nickel films, from hydrophilic to superhydrophobic. Contact angle measurement, scanning electron microscopy, and Fouriertransform infrared spectroscopy were utilized in the characterization of deposited nickel layers. Potentiodynamic polarization and electrochemical impedance spectroscopy were employed to assess the corrosion inhibition performance of inhibitor on different nickel films. Our results indicate that simultaneous increase in the surface hydrophobicity and adsorption of corrosion inhibitor strategies does not yield a better corrosion resistance and that the most effective corrosion inhibition can be obtained on the bright smooth sample after a prolonged immersion in the corrosive solution. Furthermore, we show that the contact angle alone cannot be used to indicate the corrosion inhibition capability of an inhibitor.

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