Investigation of the corrosion resistance of n-tetradecanoic acid and its hybrid film with bis-silane on copper surface in seawater

The surface morphology of n-tetradecanoic acid super-hydrophobic film was studied by contact angle measurement and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy. Its corrosion resistance was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Experimental results show that the contact angle of super-hydrophobic film is larger than 150° and its corrosion resistance has been significantly improved. The combination model of n-tetradecanoic acid molecule and copper cluster was calculated by Gaussian 98 software. At the same time, experimental results also indicate that the adhesive force between n-tetradecanoic acid molecule and copper surface is insufficient. Thus, bis-[triethoxysilylpropyl]tetrasulfide (BTESPT) was selected to link n-tetradecanoic acid and copper surface in order to enhance their interaction. The corresponding electrochemical experimental results show that n-tetradecanoic acid/bis-silane hybrid film protects substrate against corrosion and this hybrid film is very compact.