Waterborne Eco-Sustainable Sol–Gel Coatings Based on Phytic Acid Intercalated Graphene Oxide for Corrosion Protection of Metallic Surfaces

Abstract

In the past few years, corrosion protection of metal materials has become a global challenge, due to its great economic importance. For this reason, various methods have been developed to inhibit the corrosion process, such as surface treatment approaches, by employing corrosion inhibitors through the deposition of opportunely designed functional coatings, employed to preserve from corrosion damages metallic substrates. Recently, among these techniques and in order to avoid the toxic chromate-based pre-treatment coatings, silane-based coatings and films loaded with organic and inorganic corrosion inhibitors have been widely used in corrosion mitigation water-based surface treatment. In this study, the synthetic approach was devoted to create an embedded, hosted, waterborne, and eco-friendly matrix, obtained by use of the sol–gel technique, through the reaction of functional alkoxysilane cross-linking precursors, namely (3-glycidyloxypropyl)trimethoxysilane (GPTMS) and (3-aminopropyl)triethoxysilane (APTES), in the presence of graphene oxide (GO) intercalated with natural and non-toxic phytic acid (PA) molecules. As a matter of fact, all experimental results from FT-IR spectroscopy, UV–Vis analysis, and SEM confirmed that PA molecules were successfully decorated on GO. Furthermore, polarization measurements and a neutral salt spray test were used to evaluate the anticorrosive performance on aluminum and steel substrates, thus showing that the GO-PA nanofiller improved the barrier and corrosion protection properties of the developed functional silane-based coatings.

Sustainable Secondary-Raw Materials, Natural Substances and Eco-Friendly Nanomaterial-Based Approaches for Improved Surface Performances: An Overview of What They Are and How They Work

“…The results of polarization measurements and a neutral salt spray test confirmed the anticorrosive behavior on steel and aluminum substrates of the final obtained sol–gel based nanostructured hybrid coating doped with phytic acid intercalated graphene oxide [ 57 ].…”

“…As a matter of fact, the sol–gel technique represents an eco-friendly method of functionalizing fabric surfaces by depositing a thin layer with specific physical properties, chemical stability and optical transparency, thus representing an advantageous technology over the ones currently available for the introduction of specific functionality onto textile fabrics. In fact, the sol–gel method makes it feasible to create textile coatings with different implemented properties [ 57 , 143 , 144 , 145 , 146 , 147 , 148 ].…”

Phytic acid-modified graphene/cobalt oxide nanocomposites: synthesis, characterization, theoretical studies, antiproliferative properties, and catalytic activities

“…Compared with GO (0.94), GO–Co 3 O 4 and GO–Co 3 O 4 –PA nanocomposites give a relatively high ratio of I D / I G (1.02 and 0.98, respectively) due to the increase in the surface defect density of GO and the adsorption of Co 3 O 4 and PA on the surface of GO. 42,87,88…”

Perspective Chapter: Functional Sol-Gel Based Coatings for Innovative and Sustainable Applications

“…The alloy's corrosion resistance is increased by the chemical adsorption of phytic acid which forms a dense network structure on the alloy's surface and prevents the anion from coming into contact with the substrate [77]. A functional sol based on GPTMS and (3-aminopropyl)triethoxysilane (APTES) was employed in combination with GO and phytic acid for the production of anticorrosive coatings for steel and aluminum substrates [78].…”