Influence of hydrolysis time on the structure and corrosion protective performance of (3-mercaptopropyl)triethoxysilane film on copper

Films of (3-mercaptopropyl)triethoxysilane with different hydrolysis time were formed on copper surface. To evaluate the influence of hydrolysis time on structures and corrosion resistance of these films, Fourier-transform infrared spectroscopy, polarization curves, cyclic voltammetry and electrochemical impedance spectroscopy tests were performed on covered and uncovered copper specimens. Results indicate that the optimum hydrolysis time is 48 h. The film obtained in this case shows the best corrosion resistance in 3.5% (w) NaCl solution.

The hydrolysis for MPTES in ethanol-water solution within 2 and 10 h is insufficient and a minimum time of 24 h is required to obtain a well hydrolyzed silane solution.Figure optionsDownload as PowerPoint slideHighlights
► Structures of MPTES films with different hydrolysis time were shown by FTIR.
► Corrosion current density of copper electrode was remarkably reduced by MPTES film.
► The film with 48 h hydrolysis showed the best stability during CV scans.
► The long term immersion behavior of films was tested by EIS.