Evaluation the Performance of Polyaniline Graphene OxideNanocomposite Coating toward Corrosion Protection of Carbon Steel inAcidic and Saline Environments

Majority of industries are inherently faced with the problem of corrosion and steps forprotection of materials from corrosion have been of large interest to them. In this research thepotential of graphene oxide nanosheets (GO) dispersed in polyaniline (PANI) network as anefficient coating for corrosion prevention was investigated [۱]. GO was synthesized from naturalflake graphite by the modified Hummers method. Also, polyaniline was chemically synthesizedby oxidation of aniline monomer under acidic condition (۰.۵ M H۲SO۴) using potassiumpermanganate and potassium iodate as an initiator of oxidative polymerization [۲]. GO wasdispersed in a PANI solution which was dissolved in tetrahydrofuran (THF) with the aid ofultrasonic agitation and the obtained dispersion denoted as PANI-GO that was used as a thick filmfor coating the corten steel. Characterization of the PANI-GO by scanning electron microscope(SEM) revealed that GO nanosheets were well dispersed in PANI network. Anodic polarizationcurves were used to evaluate the corrosion rate of bare and PANI and PANI-GO coated electrodesin ۳.۵% NaCl, HCl ۰.۱ M and seawater [۳]. The results showed that the presence of GO in coatingsignificantly increased the corrosion potential and drastically reduced the corrosion current andcorrosion rate of corten steel. The highest protection efficiency was achieved when a PANI filmcontaining ۰.۰۰۵ g GO was used as coating on the metal surface