Synthesis And Application Of Antibacterial/Antifouling Copper-based Micro-nano Structure Composites

With the increase of marine exploitation activities and the development of marine economy,the harm caused by marine fouling organisms have gradually attracted people's attention.The development of new antifouling materials with high efficiency and environmental protection is a hotspot in the field of marine antifouling research.Cuprous oxide and its composite materials are widely used in recent years as a kind of biocides.Because of their unique structure and suitable band gap,they exhibit good visible light catalytic performance and have great application prospects in marine antifouling field.In this work,from the perspective of the morphology,particle size and chemical stability of cuprous oxide,a series of copper-based micro-nano structure composites were synthesized,and their antibacterial/anti-fouling effects were investigated.The following research results have been obtained:(1)Cu₂O nanomaterials with spherical,cubic and cubooctahedron morphology were prepared by liquid phase reduction method.In vitro antibacterial experiment results showed that different Cu₂O nanomaterials showed good antibacterial properties against E.coli and S.aureus,and their properties were also better than commercial cuprous oxide..(2)A series of Cu₂O/CuO binary nanocomposites with different particle sizes were prepared by liquid phase reduction method using copper chloride,sodium hydroxide and ascorbic acid as raw materials without adding any template.The kinetic factors in the synthesis process were investigated,and the growth mechanism of Cu₂O/CuO was proposed.The results of antibacterial activity evaluation showed that Cu₂O/CuO significantly improved the inhibition effect of S.aureus compared with Cu₂O,and Cu₂O/CuO material with larger particle size had the best antibacterial activity under natural conditions.In addition,under visible light irradiation for 150 min,the inactivation efficiency of Cu₂O/CuO to bacteria was 98%,which is about twice that of the natural condition.Meanwhile,Cu₂O/CuO also had a good photocatalytic degradation activity for MO.(3)Using graphene oxide(GO)as synthetic assistant,copper chloride,sodium hydroxide and ascorbic acid as raw materials,rGO@Cu₂O binary composites were prepared.The characterization results showed that cuprous oxide of the cube was uniformly distributed in the void between the rGO layers,and the light quantum efficiency of rGO@Cu₂O was significantly higher than that of Cu₂O.The results of activity evaluation showed that rGO@Cu₂O-1:1 had the best inhibitory effect on bacteria and MO photocatalytic degradation activity.(4)By means of"freeze-thaw"method,the above rGO@Cu₂O-1:1 was encapsulated in the polyvinyl alcohol hydrogel to prepare the rGO@Cu₂O-PVA nanocomposite hydrogel material.The characterization results showed that the rGO@Cu₂O binary compound was embedded in the structure of the hydrogel channel in the shape of cluster,and the encapsulation effect was good.The results of activity evaluation showed that the antibacterial activity of rGO@Cu₂O-PVA material was significantly enhanced under light condition,and the antibacterial rate of E.coli was 64%,while that of S.aureus was 77%.