氧化亚铜-纳米银/壳聚糖智能涂层的构筑及海生物附着规律和缓释机理研究

The vast biodiversity and complexity in fouling species is a obvious challenge that scientist have to face in order to control marine biofouling, and it also becomes the current reach focus. Therefore it especially important to explore the antifouling properties of fouling-resistant coating toward different marine organisms, based on the understanding of composition of antifouling agents and the microstructure difference in antifouling coatings. In this project, the broad spectrum and high effect nano-silver is combined with cuprous oxide of alternative morphology by the electrochemical-deposition and Sol-Gel methods for the first time so as to achieve a new composite antifouling agent, then the pH responsive functional chitosan coatings were further assembled and the formed smart Cu2O/Ag/CS composite coating,which can restrain the adhesion of both micro and macro marine creature. Furthermore, we can get super-hydrophobic and pH responsive surfaces by using nanotechnology to control the interfacial structure, and discuss the effect of experimental parameters for the crystal morphology and growth process. The smart coating could decrease the adhesion of fouling organisms at the initial stage, and attain the best dual antifouling effect by combining the sanitation and low surface energy. In addition, the adhesion of nano silver and cuprous oxide on the substrate surface was reinforced account for the strong self-polymerization ability of dopamine molecules, and the pH responsive chitosan coatings can reduce the release rate of antifouling agent in the sea water and achieve long-term antifouling behavior. In this project, we present the adhesive rules on the antifouling behavior of the functional coatings and the sustained-release mechanism towards the marine advantaged organisms of seaweed, barnacle and vast marine bacteria, based on the discussion of variation of constitute component and microstructure of the coating materials.

海洋污损生物的多样性和复杂性使得防除海洋生物附着污损成为公认的难题和研究热点,因此了解涂层的防污剂组份和微观结构差异对不同种类海洋生物的防附着行为就尤为重要。本项目首次将广谱高效的纳米银与不同形貌的氧化亚铜复合，借助电化学和溶胶凝胶方法构筑一种兼具抑制海洋微观生物和宏观生物附着的新型防污剂，进而组装pH响应的功能壳聚糖涂层，形成Cu2O/Ag/CS智能复合涂层。通过纳米技术调控复合涂层的微纳米表界面结构进而在涉海材料表面实现超疏水和pH响应等特性，达到杀菌和低表面能防污的双重结合，并探讨实验参数对晶体形貌和生长过程的影响。同时借助多巴胺分子在界面强的自聚合能力，强化纳米银或氧化亚铜在基体表面的附着，通过组装pH响应的壳聚糖涂层，减缓海洋生物的初期附着及防污剂在海洋环境中的释放速度并增加其长效防污特性。探讨智能涂层的微观结构对海藻、藤壶和海洋细菌等海洋优势生物的附着规律及防污剂缓释机理。

本项目首先探索了不同形貌、尺寸纳米银（Ag）及氧化亚铜（Cu2O）的制备工作，油浴法将纳米Ag负载在Cu2O球体表面制备复合材料。测试结果表明，Cu2O@Ag复合材料具有枣糕状的异质结构，可有效提高化学稳定性，抑制Cu2O的光腐蚀，促进ROS产生提高杀菌性能。利用原位生长法制备了具有均匀核壳结构的Ag@ Cu2O纳米颗粒并形成异质结，借助环保高效的光催化杀菌技术以实现在低铜前提下提高杀菌性能的目的。测试表明贵金属和半导体界面间的相互作用形成肖特基势垒，导致Ag@Cu2O载流子分离效率明显提高的，降低了电子空穴复合率并促进产生大量ROS，从而大幅提升材料长效杀菌性能。为了进一步改善该无机材料比表面能大，易发生团聚等造成的长效杀菌性能较弱的问题，在此基础上通过水浴法引入导电聚合物聚苯胺（PANI），其丰富的氨基极大程度地改善了Cu2O和Ag的稳定性。由于PANI牢固地把Cu2O锚定在表面官能团上，对铜离子的释放有很好的延缓作用。此外，PANI优异的电荷转移作用对于抑制Cu2O-Ag的光腐蚀，提高ROS杀菌性能也大有裨益。长效抑菌试验结果表明， 30天后PANI-Cu2O-Ag对金黄色葡萄球菌和铜绿假单胞菌的抑菌率比单独Cu2O分别提高了40%和50%。.借助二维N型半导体石墨相碳氮化合物（C3N4）和Cu2O形成P/N结异质结构的原理，利用原位生长法制备了Cu2O/ C3N4复合材料，以提高Cu2O的光催化杀菌能力。C3N4作为一种二维片状材料，能有效减缓Cu2O氧化过程并减缓铜离子释放，且利用二者之间P/N结异质结构可有效增强的载流子分离效率，促使产生大量ROS以达到高抑菌效率。相较Cu2O 210 μg/mL的最小抑菌浓度（MIC）， 复合材料MIC仅为90 μg/mL，降低了2-3倍，即可降低Cu2O的用量约57%。由于C3N4对Cu2O的保护作用以及对铜离子的缓释作用，60天后复合材料依旧表现出优异的杀菌性能。..借助壳聚糖（CS）氨基在酸性、碱性溶液中的质子化和去质子化过程，通过微乳液法制备辣椒素@壳聚糖（CAP@CS）胶囊，赋予胶囊pH响应性能，实现CAP的可控释放。由于CS可重复的质子化和去质子化过程，经过15次酸碱交替循环后，胶囊仍表现出优异的响应性能和杀菌性能，可作为新型智能防污剂应用于海洋防污领域。