Surface modification of mild steel before acrylic resin coating by hybrid ZnO/GO nanostructures to improve the corrosion protection

The synergistic effect of ZnO and GO nanostructures on the surface modification of mild steel before the acrylic resin coating was studied. Firstly, the steel surface was pretreated in the presence of ultrasonic irradiation, and then ZnO nanostructures were synthesized by the cyclic voltammetry technique. GO nanosheets prepared by the modified hummer's method were deposited on ZnO-containing surfaces using the electrophoretic deposition (EPD) technique. GO coatings with thicknesses of 2.84, 4.47 and 9.42 mu m were obtained by varying the EPD time, and the 4.47 mu m was found as the optimum value for the fabrication of hybrid ZnO/GO structures. All samples were then covered with a thin layer of acrylic resin (10 mu m) by the spin coating technique. The results indicated that the sample with underneath of hybrid ZnO/GO nanostructures shows significant improvement in anti-corrosion performance. In other words, Rp is increased from 150,000 Omega cm(2) (in the rein coated sample) to 380,000 Omega cm(2) (in the sample with hybrid nanostructures). The resulting surface has the potential to use as protective and glossy black coatings. The role of underneath nature, surface roughness, and molecular interactions between oxygen functional groups of ZnO, GO, resin, and the metal in the enhanced corrosion protection was illustrated. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.