| In modern oceanography,situ field monitoring is an important way to know current ocean state.Through fixing the optical device on the underwater equipment,the data such as turbidity,fluorescence and optical image,can be obtained and used for characterizing the local environment.When a solid surface immersed into seawater,protein and microbes will accumulate to form biofilms on the optical window surface,eventually develop into macro fouling that influences the efficiency of optical instruments.Focusing the antifouling technology on optical glass,several feasible technologies have been put forward,such as releasing organic tin copper,fungicide.However there still exists some disadvantages,such as high energy consumption,pollution of Marine environment.Therefore,looking for a way with low energy consumption and environment friendly is still a challenge.Previous studies have shown that electrochemical chlorine generation in situ is a promising way to prohibit the biofouling of optical window under the seawater.ITO(indium tin oxide)conductive glass has been reported working as anode to electrolyze seawater,but there are some disadvantages,such as short working life and high chlorine generation potential.Therefore,in this thesis,expecting to solve these problems,a graphene coating/indium tin oxide(G/ITO)composite electrode was prepared and its electrocatalytic chlorine generation activity was researched and compared with the composite electrode Pt/ITO.The experimental results show that,the chlorine generation potentials of G/ITO and Pt/ITO were 0.8V and 1.1V respectively,and the lower chlorine potential indicated that the electrocatalytic effect of graphene was better.Under same potential,the current density of G/ITO is bigger than Pt/ITO on chlorine generation.However,with continuing anode electrolysis process,the chlorine current density of G/ITO decays faster than Pt/ITO.The reason may be related to the graphene coating fall off from the ITO surface because of weak combination or concentration polarization produced in the electrolysis process.In this dissertation,learning from the structure design of heating wire used to prevent mist for the car windows,the platinum wire electrode(NW-Pt)with nano-surface structure was obtained by electrodeposition technique.Two NW-Pt threads were fixed on the surface of ordinary glass to form a double wire electrolysis system,and the electrocatalytic performance of chlorine generation was studied.SEM and EDS were used to characterize the morphology and composition of NW-Pt.Anodic polarization test technology and constant potential DC electrolytic technology were used to test electriccatalytic chlorine generation activity,lifetime and stability.3D stereo microscope was used to study the antifouling performance in diatom suspension.The results show that,the nano-sized particles constructed on the surface of platinum wire increased the specific surface area,enhanced the effective active sites of chlorine generation,thus decreased the potential of chlorine generation and increased the current density,and finally improve the performance of electrocatalytic chlorine generation.In an electrolysis cycle,two NW-Pt threads working as cathode and anode alternately,can avoid current decay of continuous anodic electrolysis,and the dispersion arrangement of the electrode wire also solves the problem that the Pt electrodeposited layer on the surface of ITO glass affects the light transmittance.The 12-day antifouling test results of diatoms as target organisms showed that,NW-Pt electrochemical chlorine-protected glass had almost no fouling biological adherence and the antifouling effect was significant. |
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