Corrosion Resistance of Copper Surface Modified with(3-Mercaptopropyl) Trimethoxysilane in NaOH Solution

Self-assembled monolayer film of(3-mercaptopropyl) trimethoxysilane(MPTS) was formed on electropolished surface to improve the corrosion resistance of copper.The structure of MPTS film was studied by using FTIR and SEM,and the inhibition effect of film was evaluated for copper in 0.5 mol/L NaOH solution using electrochemical linear polarization and AC impedance.The effects of deposit time and silane concentration were also discussed.The corrosion resistance of copper is improved markedly owing to the chemical absorption of MPTS on copper,and linear oligomer forms on the surface by cross-linking of Si-O-Si bonds.The higher is MPTS concentration,the more compact is the film.The corrosion potential of copper with MPTS film moves positive 200 mV,the corrosion current decreases an order of magnitude than that of blank copper,and the inhibition efficiency is 86.5%.MPTS monolayer retards the reduction of dissolved oxygen and inhibits the growth of copper oxide in the NaOH solution.