Electrochemical Comparison of SAN/PANI/FLG and ZnO/GO Coated Cast Iron Subject to Corrosive Environments

Abstract

ZnO/GO (Graphene Oxide) and SAN (Styrene Acrylonitrile)/PANI (Polyaniline)/FLG (Few Layers Graphene) nanocomposite coatings were produced by solution casting and sol-gel methods, respectively, to enhance corrosion resistance of ferrous based materials. Corrosive seawater and ‘produced crude oil water’ environments were selected as electrolytes for this study. Impedance and coating capacitance values obtained from Electrochemical Impedance Spectroscopy (EIS) Alternating Current (AC technique) showed enhanced corrosion resistance of nanocomposites coatings in the corrosive environments. Tafel scan Direct Current (DC technique) was used to find the corrosion rate of nanocomposite coating. SAN/PANI/FLG coating reduced the corrosion of bare metal up to 90% in seawater whereas ZnO/GO suppressed the corrosion up to 75% having the impedance value of 100 Ω. In produced water of crude oil, SAN/PANI/FLG reduced the corrosion up to 95% while ZnO/GO suppressed the corrosion up to 10%. Hybrid composites of SAN/PANI/FLG coatings have demonstrated better performances compared to ZnO/GO in the corrosive environments under investigation. This study provides fabrication of state-of-the-art novel anti corrosive nanocomposite coatings for a wide range of industrial applications. Reduced corrosion will result in increased service lifetime, durability and reliability of components and system and will in turn lead to significant cost savings.

Polyaniline Synthesized by Different Dopants for Fluorene Detection via Photoluminescence Spectroscopy

“…PANI is a singular conducting polymer compound with unique electrical and optical properties [ 10 ] and has the advantages of simple synthesis, environmental stability, affordability and flexible control of electrical features with charge-transfer doping and protonation [ 10 , 12 , 13 ]. Owing to its extraordinary properties, this compound can be used in various fields, such as electrochromic glasses [ 14 ], solar cells [ 15 ], electroluminescent machines [ 10 ], sensors [ 16 ], biosensors [ 17 ], supercapacitors [ 18 ], neural prosthesis/biotic–abiotic interfaces [ 10 ], scaffolding [ 19 ], delivery systems [ 20 ], anti-corrosion materials [ 21 ], membrane gas separation [ 8 ] and solar cells [ 22 ]. During the polymerization of aniline monomer, PANI transforms into one of the three states of normalized oxidation: (a) leucoemeraldine (white/clear), (b) pernigraniline (blue/violet) and (c) emeraldine (salt- green/base-blue).…”

Effects of Annealing on Structural, Morphological, and Corrosion Properties of α-Fe2O3 Thin Films

“…7, the Nyquist plots as expected from EIS theory were not complete semicircles, both before and after annealing. 49,50 At the film-solution interface, the electrons forming the charge on the film side are much smaller than the ions on the solution side. Therefore, to balance the charge in the double layer, the ions line up from the outer Helmholtz layer into the solution, thus preventing the formation of an ideal capacitor at the interface.…”

Review of the Application of Graphene-Based Coatings as Anticorrosion Layers

“…In crude oil-produced water, corrosion was decreased by up to 95% and 10% by the organic and inorganic coatings, respectively. The better anticorrosion properties of SAN/PANI/FLG compared to ZnO/GO were attributed to the reduced pore formation and enhanced barrier properties [74]. Another example can be the modification of graphene with 3-aminopropyltriethoxysilane (APTES) which leads to the formation of covalent bonds between graphene and the copper substrate.…”