Study On Anti-fouling Mechanism Of Cathode Current Method For Barnacles

While exploring the ocean, human face serious metal corrosion and marine biofouling. There are problems about durability, energy consumption and environmental protection in the existing main antifouling method such as coatings, electrolysis. The cathode current technology is a new kind of antifouling method, which is both used to protect the metal from sea water corrosion and to prevent biofouling. However, its anti-fouling mechanism is not clear, studies of its anti-fouling mechanism can promote the development of this technology.Firstly, electrochemical and mass transfer theories were adopted to study the electrochemical effect on the metal surface caused by cathode current, the results showed that a low DO and high OH" concentration environment was produced near the surface of metal under the effect of cathodic current. The larger the ratio of protection current density and limiting diffusion current density, the greater the concentration of O2and OH-gradient.It was studied that the relative activity rates of barnacles II larvae at17℃,21℃,25℃, with oxygen concentration changed. The results showed that the relative activity rate decreased with the concentration of dissolved oxygen decreasing, the higher the temperature, the weaker the tolerance of larvae to low dissolved oxygen environment at temperature between17and25℃.In the microbial membrane it was found that O2and OH-concentration gradient effect could inhibit the formation of microbial membrane. The attachment of microorganisms was significantly inhibited when pH value was above9.5, the number of microorganisms attached declined with dissolved oxygen concentration at0.5mg/LThe growth curve of Chlorella under different polarization potentials showed that polarization state of the system will impact the individual’s life activities and population of Chlorella. With cathodic polarization potential under-870mV, the population have shown a downward trend.Experiments results based on O2and OH-concentration gradient effect showed that the cathode current would suppress the life of barnacles larvae in the area on the surface of metal, as well as the biofilm formation and Chlorella, which resulted in the antifouling effect.