Effect of graphene on the electrochemical protection of zinc‐rich coatings

Abstract

The effect of graphene on electrochemical protection of zinc‐rich coatings was studied by electrochemical impedance spectroscopy (EIS) and the monitoring of open circuit potential (OCP) versus time of immersion. The obtained results show that addition of 2.5 wt% graphene to zinc‐rich coating prolongs the lifetime of cathodic protection to mild steel immersion in sodium chloride solution. On the basis of these consistent finds, two protective mechanisms of graphene are assumed. On the one hand, the embedded graphene could serve as electrical conduction paths between zinc particles. On the other hand, the more distributed graphene may lead to the galvanic corrosion of mild steel.

Investigation of Cathodic Protection, Morphological, Rheological, and Mechanical Properties of Graphene/Iron Oxide Nanoparticle-Embedded Cold Galvanizing Compounds at Reduced Pigment Volume Concentration

“…This phenomenon indicated that Fe 2 O 3 /NGr particles inhibited the cathodic reduction reaction in the system, which suggests that the cathodic reduction reaction is directly proportional to the addition of conducting particles and the percolation path. , The highly conductive NGr filled the voids between the spherical Zn particles, as confirmed by FE-SEM images. It interconnected the particles, enhanced the conductivity, and reached the galvanic action required to provide cathodic protection. , The GC-5 showed more galvanic action than GC-3 and GC-4 because of the higher amount of NGr (1.5%).…”

“…It interconnected the particles, enhanced the conductivity, and reached the galvanic action required to provide cathodic protection. 28,44 The GC-5 showed more galvanic action than GC-3 and GC-4 because of the higher amount of NGr (1.5%).…”

“… 24 − 26 It can be added to the polymer matrix to enhance the electrical connection by filling the voids. 27 , 28 Red iron oxide (Fe 2 O 3 ) is a standard crystalline anticorrosive pigment widely used in protective coatings. The nanodimensional Fe 2 O 3 has recently received considerable interest due to its exceptional features, such as good anticorrosion properties and a large surface area to volume ratio.…”

“…It is a two-dimensional material that displays high crystallinity and electronic-friendly behavior. It offers high electrical mobility (2.5 × 10 5 cm 2 V 1 S –1 ), superior mechanical properties (1 TPa Young’s modulus), very high thermal conductivity (>3000 W mK –1 ), chemical inertness, an excellent energy barrier, and large specific surface area. − It can be added to the polymer matrix to enhance the electrical connection by filling the voids. , Red iron oxide (Fe 2 O 3 ) is a standard crystalline anticorrosive pigment widely used in protective coatings. The nanodimensional Fe 2 O 3 has recently received considerable interest due to its exceptional features, such as good anticorrosion properties and a large surface area to volume ratio …”

Incorporation of different proportions of polytetrafluoroethylene and graphene into polyethersulfone matrix as efficient anticorrosive coatings

“…Graphene, a phenomenal nanomaterial, has drawn huge attention over the past decade, owing to its strictly two‐dimensional structure, giant carrier mobility, high thermal conductivity, and brilliant mechanical properties . To date, the use of graphene as a corrosion protection barrier has been widely reported, based on its shielding effect (impermeability to oxygen, water, and chloride ions) and excellent electrical conductivity. However, graphene sheets can easily aggregate together owing to their high specific surface area and strong van der Waals forces, which limits their applications in polymer composites .…”