Studying the effects of surface modification of Cr sub(2)O sub(3) nanoparticles by 3-aminopropyltrimethoxysilane (APTMS) on its corrosion inhibitive performance

• Published in: Journal of sol-gel science and technology 2015-01, Vol.73 (1), p.141-153
• Main Authors: Palimi, MJ, Rostami, M, Mahdavian, M, Ramezanzadeh, B
• Format: Article
• Language: English
• Subjects: Carbon steels; Chromium oxides; Corrosion; Electrochemical impedance spectroscopy; Grafting; Nanoparticles; Panels; Pigments; Steels
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-014-3505-3

Cr sub(2)O sub(3) nanoparticles were modified with 3-aminopropyltrimethoxysilane (APTMS). The APTMS grafting on the surface of the nanoparticles was analyzed by turbidimeter, thermal gravimetric analysis and Fourier transform infrared spectroscopy. The corrosion performance of the mild steel panels immersed in the 3.5 wt% NaCl solutions containing modified and unmodified pigments extracts was studied by electrochemical impedance spectroscopy and linear polarization techniques. The surface morphology of the samples was characterized by scanning electron microscopy. The type and concentration of the released ions from the pigments were measured by inductively coupled plasma. Results revealed that APTMS grafted on the surface of nanoparticles successfully. It was found that Cr sub(2)O sub(3) nanoparticles released inhibitive species causing the decrease of corrosion rate of the steel sample in the 3.5 wt% NaCl solution. However, the unmodified nanoparticles released higher ions and showed better inhibitive performance than the modified one. A lower surface degradation of the steel specimen exposed to the solution containing unmodified pigment extract was observed compared to the modified one.