Preparation Of Photocatalytic Nanoparticles Composite Zinc Coating And Research On Their Antifouling Mechanism

Microbial corrosion and biofouling are important problems in the service of marine equipment.Therefore,it is of great significance to develop a new type of pollution prevention technology with high efficiency and no pollution.In this paper,by using electrodeposition method and adding photocatalyst nanoparticles into sulfate bath system,the composite coating of photocatalyst nano particles and zinc was successfully prepared on the surface of carbon steel.The electrodeposition process and the influence of additives on the electrodeposition process were studied by means of electrochemical test,X-ray crystal diffraction(XRD),scanning electron microscope(SEM).The composite state and composite amount of photocatalysis nano particles in the coating were studied by means of EDS.the antibacterial properties of the composite coating were tested with Escherichia coli,marine monocytogenes and Bacillus as representative bacteria.Finally,the antibacterial mechanism of the composite coating was deduced according to the photocatalysis mechanism of the added photocatalysis nano particles.Mainly research contents are shown as follows:1.Firstly,nano bismuth phosphate particles were successfully prepared by hydrothermal method,and then bismuth phosphate zinc composite coating was successfully prepared by constant current method with the aid of ultrasonic and chemical dispersant.It was proved by material characterization that nano bismuth phosphate was successfully compounded into zinc coating,and the chemical dispersant edta-2na and 30 W ultrasonic assisted can greatly improve the composite amount of bismuth phosphate in the layer.1.Finally,the photocatalytic antibacterial properties ofthe composite coating were tested by E.coli,marine monocytogenes and Bacillus.It was found that the composite coating has superior antibacterial properties,and the composite amount is directly proportional to the antibacterial rate.2.Firstly,the urchin like bismuth sulfide nanoparticles with photocatalytic antibacterial properties were prepared by hydrothermal method,and then a series of bismuth sulfide-zinc composite coatings were prepared on 20# carbon steel.By means of deposition potential,SEM,EDS,XRD and other means,the deposition process of coating and composite mechanism of bismuth sulfide were studied.Finally,E.coli was used as a representative bacteria to test the photocatalytic antibacterial performance of the composite coating.The results showed that bismuth sulfide-zinc composite coating had good antibacterial performance against E.coli under visible light,and the higher the composite content of bismuth sulfide,the better the antibacterial effect.3.Firstly,nano bismuth molybdate with uniform morphology were successfully prepared by hydrothermal method,and then nano molybdate were added into the sulfate zinc plating solution.The nanometer bismuth molybdate-zinc composite coatings were prepared with the aid of 30 W ultrasonic.It was proved by material characterization that nano bismuth molybdatee was successfully compounded into zinc coating.The antibacterial control experiment of the composite coating in dark and light conditions were tested by E.coli as a representative bacteria.It was found that the composite coating had no antibacterial properties in dark conditions,but had good antibacterial properties in visible light,which proves that bismuth molybdate itself is non-toxic to bacteria,and its antibacterial effect in light condition is caused by the photocatalytic activity of bismuth molybdate.