| Aluminum?Al?and its alloys are abundant engineering materials with extensive applications in daily life,which include construction,aerospace,shipping industries,automotive industries,and household items because of their excellent physical and mechanical properties.Aluminium is oftens subjected to electrochemical anodising to form a porous coating.Graphene is a single atomic nanosheets of carbon,which was considered as an ultra-thin protective coaing.In this paper,graphene was in situ functionalized in a one step process to solve graphene agglomerate,during the exfoliation of graphite rod.Subsequently,graphene and modified graphene were respectively obtained by anodic electrophoretic deposition on anodized aluminum oxide film,hydrophobic properties and the corrosion resistance was studied.The electrolyte was prepared by dissolving 0.1M?NH4?2SO4 containing KH550?aminopropyltriethoxysilane?.Electrochemical exfoliation was carried out by applying a potential of 10V vs titanium wire,under the condition of 70°C water bath.Graphene was prepared by electrochemical exfoliation in a 0.1M?NH4?2SO4 solution.FTIR showed that silane was successfully grafted on graphene,indicating that one-step electrochemical exfoliation and in-situ functionalization were feasible to prepare KH550-graphene.TG found that KH550-graphene has higher thermal stability than graphene;XRD and Raman showed that the lattice structure of graphite is retained during the electrochemical stripping process,and the KH550-graphene defect is higher than that of graphene.SEM showed no obvious agglomeration on the surface of KH550-graphene;graphene was found to be superior to KH550-graphene in different solution stability analysis.Porous aluminum films were prepared by a conventional anodizing method in a0.3M oxalic acid solution at a constant potential of 50V and 25?.After the preparation of suspension of 0.2 mg/ml graphene in isopropanol,graphene coatings with different corrosion resistance and surface morphology were deposited by anodic electrophoretic deposion method by adopting different applied voltages.The effects of different deposition voltage parameters on the surface morphology and corrosion resistance of coatings were studied.The electrochemical performance of the obtained graphene composite film was tested.The corrosion resistance of the graphene composite film obtained at 70V deposition voltage was found.The best performance is compared with the porous alumina film impedance?79.97k?·cm2?,the film has a large impedance?385.4k?·cm2?,and the self-corrosion potential is?-0.762V?in a 3.5%NaCl solution.The corrosion current density has a value of(20.66nA·cm-2).The KH550-graphene coatings were deposited on the surface of the porous aluminum film by the same deposition method.The contact angle test of the silane graphene composite coatings and the graphene composite coatings deposited by different voltage.Results showed that the modification of graphene by KH550 and the different deposition voltages affected the hydrophobic properties of the coatings.The KH550-graphene coatings were larger than the contact angle of the graphene coatings,and the water contact angle of the KH550-graphene coatings at 150V is 140.1°,which closed to the contact angle of the superhydrophobic surface is 150°. |
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