Corrosion resistance of 3,4-dihydroxyphenylalanine/octadecylamine complex coatings on copper substrate



Octadecylamine (ODA) film assisted with the preferential adhesion of poly-DOPA was prepared on copper substrates by dip-coating method. The DOPA self-polymerized and adhered membrane was firmed to the copper substrate in mild aqueous alkaline environments. By immersing the substrate coated with poly-DOPA in its absolute ethyl alcohol solution, ODA was adsorbed onto the substrate to give a hydrophobic surface. The formation and surface structure of the film were characterized by water contact angle measurement (DA), and scanning electron microscopy. The corrosion behavior of the functional hybrid films was evaluated by electrochemical impedance spectroscopy. Experimental results show that the impedance of the composite films reaches to 106 Ω, enhancing anti-corrosion property of copper surface greatly.