Corrosion resistance and antibacterial properties of hydrophobic modified Ce-doped micro-arc oxidation coating
Erhui Yang, Ruixia Yang, Wu Wei, Qiufeng Mo, Feiyan Liang, Dong Li, Weizhou Li
Abstract
Aluminium (Al) alloys with high corrosion resistance and bactericidal capability will have significant potential for broader utilization in marine applications. To achieve this, a layer of cerium (Ce)-doped anodic oxidation (AO) film was prepared on the surface of the Al alloy to modify the pore structure of the micro-arc oxidation (MAO) coating. This not only improved its corrosion resistance but also imparted certain antibacterial properties to the coating. Then, 1H, 1H, 2H, 2H- perfluoroalkyl triethyloxy-silane (PFOTES) was used to hydrophobically modify the coating, which more effectively obstructed corrosive ions and bacteria, further elevating its corrosion resistance and antibacterial properties. Electrochemical tests demonstrated that |Z|0.01Hz of the modified coating was 2.86 × 109 Ω cm2 which was two orders of magnitude higher than before. Furthermore, it remained above 109 Ω cm2 even after 288 h of immersion. Moreover, the antibacterial effectiveness of the modified coating against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) increased by 5.89 % and 19.53 %, respectively, to 98.58 % and 97.34 %. These findings indicate a promising direction for improving the corrosion resistance of MAO coatings on metallic materials, paving the way for large-scale industrialization.