| Since the era of ocean development and the development of marine resources hasbacomed, the area of maritime transport, harbor and coastal defense construction needmore than10million tons of copper alloy. Under normal circumstances, copper islisted as one of the corrosion resistance of metal because of its more positive potentialthan hydrogen (+0.35V), so hydrogen depolarization does not occur. However, as thetime continued，copper will usually be damaged in the form of corrosion, fracture,especially in harsh environments, such as chloride, sulfide, which limit its broaderapplication.Recently, mussel adhesive proteins excreted by marine mussels have attractedmuch attention because of their ability to form strong adhesive interaction withvarious substrates in wet environment. So, many research scholars reported theliterature. Dopamine (DA, also known as3-hydroxy tyramine) as the hypothalamusand pituitary gland catecholamine neurotransmitter, which plays an important role inthe area of the health and disease control, prevention. Because of its high strength,high toughness and water resistance, therefore it has broad application prospects. Thispaper uses the catechol group in the dopamine adsorpted on the copper surface bydip-coating method, which is contributed to the adsorption of the11-mercaptoundecanoic acid (MUA) and11-mercaptoundecanoic acid (MUA)/1-dodecanethiol (SH) complex film. The structure and properties of the compositefilms were characterized using X-ray diffraction, scanning electron microscopy,contact angle measurements, potentiodynamic polarization curves andelectrochemical impedance spectroscopy (EIS). The results indicated that theadsorption of the MUA film makes the coating more dense, which indeed enhance thecorrosion resistance than pure copper and the polydopamine film modified surface.More importantly, the anode curve obtained from potentiodynamic polarizationemerges a passivated platform, which indicates that the MUA/SH coating prevents the erosion of chloride ions within a certain range.According to the contact angle of the dopamine assisted1-dodecanethiol coatinghard to improve, micro and nano copper was deposited on the copper substrate byelectrochemical deposition in order to build surface roughness. Many factors, such astemperature, concentration, voltage, and N2, can effect the morphology ofmicro-nano-copper. Then, the polydopamine assisted1-dodecanethiol films werefabricated by dipping as-deposited surface into an aqueous alkaline dopamine solutionsolution and1-dodecanethiol ethanol solution, and the modified surface showedsuper-hydrophobicity. the study found that the addition of micro-nano-copper changedthe topography of the super-hydrophobicity surface. The wettability properties of thesuper hydrophobic surface after exposure in air and immersion in3.5wt.%NaClsolution for different time were estimated using static water contact anglemeasurement. The averaged contact angle of the modified surface has no muchchange after exposure in air for35days, and It is clear that there is slightly change ofthe water CAs on the fabricated surface after immersion in3.5wt.%NaCl solutionafter35days, showing the long-term stability of the fabricated surface. The EISresults show that the corrosion resistance of super-hydrophobic film is superior to thehydrophobic membrane and still have a good corrosion resistance after immersion for35days. Although the corrosion product occur on the copper surface after immersionin3.5Wt.%NaCl solution for35days, the corrosion resistance of the modifiedsurface is larger than that of the bare copper with the immersion time increases to35day. Therefore, the electricity deposited method was used to fabricate the micro/nanostructured copper on copper surface, which can effectively protect the coppersubstrate from the erosion of Cl-in sea water. |
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