Volume 2013 (2013), Article ID 142493, 9 pages
Corrosion Protection of AA7075 Aluminium Alloy by Trimethoxy-Silanes Self-Assembled Monolayers
1Materials Metrology Division (Dimat), National Institute of Metrology, Quality and Technology (Inmetro), 25250-020 Duque de Caxias, RJ, Brazil
2Department of Chemistry, Federal University of São Carlos (UFSCar), 13565-905 São Carlos, SP, Brazil
3Laboratory of Interfacial Electrochemistry, Department of Physical Chemistry, Institute of Chemistry of São Carlos (IQSC), University of São Paulo (USP), 13560-970 São Carlos, SP, Brazil
Received 31 January 2013; Accepted 28 February 2013
Academic Editors: A. I. Bhatt, A. C. Chialvo, A. Guerrieri, and A. A. Moya
Copyright © 2013 Rodrigo S. Neves et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
This study presents electrochemical data concerning the aluminium alloy AA7075 surface modified by self-assembled monolayers (SAMs) of octadecyl-trimethoxy-silane and propyl-trimethoxy-silane. Polarisation curves have shown SAMs blocking effect, as they partially block the oxygen reduction reaction and displace the corrosion potential to positive values. Electrochemical impedance spectroscopy experiments have suggested that the protective effect comes from the oxide layer stabilization by the organic monolayers, which block the corroding species diffusion to the surface. These results show the potential of using methoxy-silanes SAMs as corrosion protective coatings; however, they are also indicative of the superior octadecyl-trimethoxy-silane protective characteristics.