CAS Key Laboratory of Marine Environmental Corrosion and Bio-Fouling, Institute of Oceanology, Chinese Academy of Sciences, No.7 Nanhai Road, Qingdao 266071, China.
Open Studio for Marine Corrosion and Protection, Pilot National Laboratory for Marine Science and Technology (Qingdao), No.1 Wenhai Road, Qingdao 266235, China.
Molecules. 2019 May 22;24(10):1974. doi: 10.3390/molecules24101974.
Microbial corrosion is a universal phenomenon in salt water media such as seawater and wastewater environments. As a kind of efficient protective metal coating for steel, the damage of the Zn-Ni alloy coating was found to be accelerated under microbial corrosive conditions. To solve this problem, chitosan, which is considered a natural product with high antibacterial efficiency, was added to Zn-Ni electrolytes as a functional ingredient of electrodeposited Zn-Ni-chitosan coatings. It was found that the addition of chitosan significantly and negatively shifted the electrodeposition potentials and influenced the Ni contents, the phase composition, and the surface morphologies. By exposing the coatings in a sulfate-reducing bacteria medium, the microbial corrosion resistance was investigated. The results showed that compared to the Zn-Ni alloy coating, Zn-Ni-chitosan coatings showed obvious inhibiting effects on sulfate-reducing bacteria (SRB) and the corrosion rates of these coatings were mitigated to some degree. Further research on the coatings immersed in an -suspended phosphate buffer saline medium showed that the bacteria attachment on the coating surface was effectively reduced, which indicated enhanced antibacterial properties. As a result, the Zn-Ni-chitosan coatings showed remarkably enhanced anticorrosive and antibacterial properties.
微生物腐蚀是海水和废水等盐水环境中普遍存在的现象。锌镍合金作为一种高效的钢用防护金属涂层，在微生物腐蚀性环境下的破坏速度会加快。为了解决这个问题，将壳聚糖作为一种具有高效抑菌性能的天然产物，添加到 Zn-Ni 电解液中作为电沉积 Zn-Ni-壳聚糖涂层的功能成分。结果发现，壳聚糖的添加显著地、负向地改变了电沉积电位，并影响了 Ni 含量、相组成和表面形貌。通过将涂层暴露在硫酸盐还原菌介质中，研究了其微生物腐蚀性。结果表明，与 Zn-Ni 合金涂层相比，Zn-Ni-壳聚糖涂层对硫酸盐还原菌（SRB）具有明显的抑制作用，这些涂层的腐蚀速率在一定程度上得到了缓解。进一步研究了浸泡在含悬浮磷酸盐缓冲生理盐水介质中的涂层，结果表明，涂层表面的细菌附着得到了有效减少，表明其具有增强的抗菌性能。因此，Zn-Ni-壳聚糖涂层表现出显著增强的耐腐蚀性和抗菌性。
