Preparation Of Graphene-silica Composite Nanocontainer By Electrodeposition And Its Application In Protective Coatings

Graphene is one of the most popular two-dimensional nanomaterials and the hot points of scientific research in many fields since it was successfully separated.Due to its excellent blocking performance,low gas/liquid permeability and high chemical/thermal stability,graphene has been tried applying to the metal corrosion protection in recent years.While,current study results reflect that graphene is not suitable for protective layer directly because it will accelerate the corrosion of metals.And graphene composite coatings have relatively better protective ability but only played as passive protection from corrosive mediums.Therefore,how to keep the physical blocking performance of graphene,and at the same time,develop the active protection to raise the long-term protection performance of graphene composite coating,is the demand and technical difficulty of graphene coating industry.In this paper,based on the sol-gel electrochemical deposition technology,sub-micron mesoporous silica is deposited onto the smooth surface of graphene powder electrode.Then,corrosion inhibitor are encapsulated in the container and infiltered into the coating to improve protection property of the coating.The main contents are listed as follows:?1?Electrodeposition of SiO2 on the graphene surface?G-eSiO₂?and the study of its performance.The electrodeposition is performed in a self-made device in which graphene is used as work electrode.SEM and TEM images show sub-micron mesoporous SiO2 is successfully deposited onto the surface of graphene and performs high binding force between them.What's more,the influence of different deposition potential and deposition time on the film thickness are also investigated.It shows that this technology has strong regulation and set a good foundation for the preparation of different functional composite materials.?2?The application of G-eSiO₂ in metal corrosion protection.Using G-eSiO₂ to load inhibitor?benzotriazole,BTA?and then doping in the polyvinyl butyral?PVB?coating to improves the anti-corrosion performance for copper.Salt water immersion test,copper dissolution experiments and electrochemical impedance spectroscopy suggest that the coating with the doping of G-eSiO₂/BTA has better protective effect and can greatly reduce the corrosion rate of copper.