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Abstract

This research endeavors to utilize electrophoretic deposition (EPD) to coat copper (Cu) pipes with graphene oxide (GO) nanosheets, aiming to bolster their resistance against corrosion. To achieve this, a stable aqueous colloidal suspension of GO was meticulously prepared via liquid exfoliation in deionized water. This suspension served as an electrolytic solution for EPD. The EPD process involved the meticulous application of varied operational parameters such as deposition time, applied voltage, and GO nanosheet concentration to facilitate anodic deposition on the copper pipe’s surface. To gauge the efficacy of the GO coating, evaluations were conducted to assess adhesive force and stabilization using specialized coating adhesion scratch testing equipment. Further analysis of the resulting film on the Cu pipe was executed employing X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and Fourier transform infrared spectroscopy (FT-IR). These methods provided detailed insights into the characteristics and properties of the GO material post-deposition. The study yielded noteworthy outcomes, revealing the achievement of a uniform, unbroken, and consistent coating film on the Cu pipe. This was accomplished by employing specific parameters as 60 s of deposition time, a GO concentration of 0.5 mg/mL, and a voltage of 20 V. Impressively, when subjected to a corrosive solution containing 3.5% sodium chloride, the corrosion protection exhibited a remarkable twofold enhancement compared to untreated copper tubing, boasting an efficiency (η) of 90.48%. These findings suggest that the Cu pipe, coated with GO using the EPD technique, holds significant promise for utilization in demanding industrial settings susceptible to corrosion challenges.

Keywords

Graphene oxide corrosion protection electrophoretic deposition copper pipe thin film polymeric composites

Introduction

In metallic industries, corrosion prevention plays a significant role in protecting the lifespan of the metal and preventing contamination. Copper metals are widely used for different applications such as condensers for a water desalination plant. The frequent contact of the copper to the water makes it susceptible to corrosion due to its chemical reaction to nature limiting its application. Corrosion of metals occurs when there is an interaction of the copper with non-inert surroundings such as seawater and moist oxygen from the atmosphere¹ The presence of chlorine ions in the seawater attacks copper very harshly, thereby causing corrosion. It is, therefore, necessary to develop efficient and long-lasting corrosion-resistant coating to prevent the metal from corroding.² The advent of science and technology in the nanoscale made it possible to design environmentally friendly, robust oxidation and coatings that are resistant to corrosion to prolong the lifespan of the material, even under hard environmental conditions. In recent years, researchers have focused their attention on barrier films where liquid phase deposition is used; ceramic coatings³ coatings from epoxy (polyaniline, etc.), and film coatings such as polymers⁴ among others. Among all these, graphene oxide coatings are mostly investigated due to their electrical, optical, mechanical, and some other physical properties. Graphene oxide has a strong potential to be used as a transparent film with high conductivity in composite material and some other applications at the industrial levels.

Graphene oxide (GO) is a 2D material of single thick honeycomb atomic crystal lattice of allotropes of carbon composed of tightly packed sp² hybridized carbon atoms with the ability to remain exfoliated as a single layer of atoms in water. It has high mobility of electron (250,000 cm²/V) due to its free electrons, effects of the quantum hall at ambient temperature and ballistic transport.⁵ Various researchers have used solution based to deposit 2D graphene oxide on conductive material, including thermal decomposition, chemical deposition,⁶ layer by layer coating,⁷ filtration by membrane,⁸ physical vapor deposition,⁹ spin coating.¹⁰ However, most of these methods use high temperature instead of low temperature. The low-temperature deposition has a lot of advantages over high-temperature techniques.¹¹ Application of high temperature techniques such as Langmuir-Blogget, inkjet printing makes it difficult in assembling graphene layers due to the complexity of its instrumentation and high temperature.¹⁰ Electrophoretic (EPD) deposition is an example of a colloidal deposition route that uses low pressure and room temperature process. Recently, EPD has attracted much attention as a method of fabricating a nano-sized, thin composite film on a conducting material with a wide range of applications, simple and low cost.¹¹

The report shows that researchers have used graphene oxide layers to prevent metallic materials from corroding. Raman et al. reported Chemical Vapor Deposition (CVD) technique for coating graphene on copper which showed impedance of the copper to degradation of the electrochemical increasing with the reduction in the cathodic and anodic current densities of the coated copper.¹² Kang et al coated reduced graphene sheets on iron and copper foils to improve upon their resistance corrosion by oxidation. This was prepared by the transfer of the reduced graphene oxide multilayer from silicon oxide (SiO₂) substrate.¹³ Kirkland et al studied the properties of GO using CVD technique as a barrier for corrosion on copper and nickel.¹⁴ Successful results have been achieved in depositing graphene oxide sheet on a metallic substrate employing the EPD technique. Raza et al employed EPD method for depositing GO on copper sheets using different parameters. The corrosion rate results after the experiment were outstandingly lower than the bare copper.¹⁵ Singh et al prepared GO polymer composite coating by EPD method. Results showed that the inhibition efficiency increased much more than the bare copper.¹⁶

Most of the failures in corrosion resulting from coating through the usage of the different technique have shown to be as a result of defects in the coating.¹⁷ The coating adhesion on the surface of the metal plays a key role in the efficacy of the coating in prevention corrosion.¹⁸ EPD deposition has proved beyond doubt in producing a uniform and homogenous with fantastic adhesion coating. This breaks the barrier of the defects associated with coating. This is a simple technique where charged particles of colloids dispersed in a liquid medium, move with the influence of electric current to the cathode through the application of a DC voltage.¹⁹ The technique is versatile, rapid, and easy in controlling thickness, rate of deposition, coatings uniformity, and concentration of suspension. EPD involves the use of organic fluids as a suspending media due to their excellent stability chemically, high density, and it’s less conductive.²⁰ However, the use of inorganic fluid or aqueous medium is effective and advantageous as lower voltage, less cost, and risk of explosion is minimal.²¹ These advantages attracted researchers’ interest in using water as the solvent for graphene oxide in preparing the colloidal suspension for corrosion protection.¹⁵ This study is aimed at developing graphene oxide (GO) coating on a copper pipe from transparent colloidal suspension in the aqueous medium by electrophoretic (EPD). The objective is to (i) to characterize the as-synthesize GO and the coatings using various characterization techniques; (ii) to examine the efficacy of the coatings preventing the copper pipe from undergoing oxidation and corrosion using electrochemical impedance (EIS) in NaCl by direct testing of the copper pipe’s coatings for corrosion protection.

Experimental work

Materials and chemicals

A copper pipe with a purity of 99%, procured from the market, served as the foundational substrate for the EPD coatings in this study. To prepare its surface, a meticulous process was followed. Initially, the copper sheet underwent polishing using 400 and 200 grit carbide paper of silicon to eliminate any contaminants and activate surface atoms, facilitating improved adhesion. Subsequently, it underwent ultrasonication with acetone for 20 min, followed by rinsing with distilled water, and ultimately air-dried at room temperature. For the synthesis of graphene oxide (GO), graphite powder with an average particle size of 10 µm was utilized as the precursor material. The chemicals employed in the process including analytical-grade sulfuric acid (H₂SO₄), hydrogen peroxide (H₂O₂), potassium permanganate (KMnO₄), nitric acid (HNO₃), hydrochloric acid (HCl), and acetone were procured from Sigma Aldrich, ensuring high-quality standards throughout the experimental procedure.

Graphene oxide synthesis

Modified Hummers method²² was used in synthesizing graphene oxide. In brief, 10 g of graphene powder was added to 160 mL of HNO₃ and 200 mL H₂SO₄ under continuous stirring and ultrasonication using (Cole-Parmer, USA). 60 g of KMnO₄ was added dropwise (1 g/min) to the mixture under ice bath and vigorous stirring for 4 days to improve the powder’s degree of oxidation. The resulting mixture was transferred carefully into a two-necked round bottomed flask containing 1 L of distilled ice. 20 mL of H₂O₂ (30%) was slowly added dropwise maintaining the temperature at 60°C till the color of the mixture changed from brown to yellow gradually, indicating the climax of the reaction. 100 mL HCl was used to wash the solution and stirred for 1°h for three consecutive days. The residual ions were further washed with distilled water. Furthermore, the centrifuge was used to separate the supernatant till a neutral pH was attained, dried at 60°C for 12 h, thus GO flakes obtained.

Preparation of graphene oxide suspension

As reported by,²³ 260 mg of the synthesized graphene oxide was dispersed in 260 mL distilled water and sonicated for a period of 2 h. The suspension after 2 h was left to settle for about 24 h. The settled graphene oxide was decanted from the stable colloidal suspension. The graphene oxide sediment was dried and measured and the concentration of the stable colloidal suspension was determined by arithmetic calculation (0.6 mg/mL) indicating GO’s maximum solubility in water.²⁴ The liquid suspension’s concentration was modified utilizing distilled water to reach a concentration of 0.5 mg/mL.

Sample preparation for electrophoretic deposition (EPD) of GO on Cu pipe

The suspension of graphene with 0.5 mg/mL concentration was attained by dissolving graphene nanosheets (30 mg) with 1∼3 μm diameter, 1∼5 nm thickness, and 99.9% purity mixed in 60 mL ethanol and isopropanol solution. The obtained solution was sonicated for 1 h to completely disperse it for EPD. Prior to EPD, copper pipe with 3/9 in its outer diameter from a local market in Alexandria, Egypt was cut 7 cm long utilized as anode was polished mechanically using a grinding paper made from silicon carbide (SiC) with (grit size range of 2000) to remove the layer of oxide from the copper pipe. Surface smoothness increases rate of adhesion and subsequently coating.²⁵ Then the pipe was sonicated for 20 min in acetone to eliminate organic contaminant and finally rinsed in distilled water. A stainless-steel pipe was used to surround the anode and cathode aligned with Teflon ring at a fixed distance of 10 mm as seen in Figure 1d. The technique of EPD was in various voltages (3-10 V) and deposition time (15-90 s) applied utilizing a DC power source (Model: TB160V22A1080 W, Matsasuda, Japan).

Figure 1.

(a) Chemical oxidation of graphite (G), (b) GO liquid exfoliation and ultrasonication, (c) stable aqueous suspension of GO, (d) Schematic diagram of the EPD technique, and (e) Cu pipe coated with GO by EPD.

Characterization

Scanning electron microscopy (SEM) images of G, GO and the various copper coatings were taken using JOEL-JSM 6010LV. X-ray diffraction (XRD) pattern was captured with (Shimadzu XRD-6100) loaded with Cu Kα of radiation for λ=1.54 $Å$ . The GO and GO coated on copper absorption peaks were obtained from the UV-spectrophotometer (Model: Hitachi U-3900, Japan). Fourier transform infrared spectroscopy, FT-IR (Bruker-Vertex 70) was conducted on the GO and GO coated copper over a scan range of 350-8000 cm⁻¹. Raman scattering test was conducted using Raman-spectrometer (Lambda solutions dimensions-P2 Raman systems) equipped with a detector (Pelletier-TE-cooled CCD) and wave-numbers coverage, 140-3000 cm⁻¹. Transmission electron microscopy (TEM) imaging was scanned utilizing (JEOL JEM-2100F). A Perkin Elmer (Lambda 35 UV/Vis Spectrometer) was used to record UV measurements. An ultrasonicated product of GO suspension in deionized water was utilized for the analysis. The ultrasonication was carried out with Ulso Hi-tech Sonosmacher (ULH-700S @ 19.83 Hz). Adhesion test was carried out on EPD-GO coated copper pipe through adhesion scratch test. In the course of the test, 3 mm long scratches were carried out on the coatings for the various samples by utilizing a 0.25 mm diamond indenter at constant speed drawn under progressive load and across the samples which ranges from 0 to 40 N. The adhesion tests of the coatings were measure through friction mode.^26–28 The point of failure is noted when the coating cracks. The corrosion resistance of the samples immersed in a 3.5 wt% NaCl solution was assessed using an electrochemical workstation integrated with a Potentiostat (specifically, a Gamry instrument, model 3000), utilizing a three-electrode cell system. The working electrode selected for this evaluation was a copper pipe, while the reference electrode employed was an Ag/AgCl electrode saturated with KCl. The counter electrode utilized in the setup was constructed from graphite. All electrodes were submerged in the electrolyte, and the Potentiostat was connected to these electrodes within the electrolyte.

To evaluate the corrosion behavior, the open circuit potential (OCP) was continuously monitored until reaching a stable value. Following the OCP recordings, polarization (Tafel) scans were conducted at a scan rate of 1 mV/s, ranging from −0.5 V to +0.5 V. Additionally, electrochemical impedance spectroscopy (EIS) was carried out at the OCP, encompassing a spectrum of frequencies from 100,000 to 0.010 Hz with a voltage amplitude of 0.01 V. From the polarization curves, the corrosion current density ( $i_{c o r r}$ ) and corrosion potential ( $E_{c o r r}$ ) were derived. Furthermore, resistance efficiency, equivalent weight (EW) of the copper pipe, and the efficiency (η) of both the bare copper pipe and the EPD-GO coated copper pipe were extrapolated and analyzed as part of the assessment process.

Results and discussion

The pattern of XRD of the graphite, graphite oxide, and graphene coated layers are shown in Figure 2. The pattern of the graphite indicated a sharp and strong peak at 26.50°, which correspond to (002) calculated utilizing Braggs equation (1) planes of graphite (pristine) indicating a highly layer of organized structure of graphite where $λ$ represents wavelength of electrons equal to 0.15,406 nm with n as an integer equaling to 1. The spacing of the layer was calculated as 0.337 nm and a peak corresponding to (001) at 2θ = 10.5° of graphite oxide. The increase in spacing (0.829 nm) indicated an outstanding change in the layer of spacing higher than graphite, which confirms the complete oxidization of the graphite. The layer of GO on the substrate displayed broad peak of diffraction at 2θ = 24.69° which corresponds to (002) of amorphous structure of graphite which confirms GO reduction during the process of EPD as shown in Table 1.

n λ = 2 d \sin θ

(1)

Figure 2.

XRD diagrams for (a) graphite, (b) graphite oxide, and (c) EPD-GO coated cu pipe.

Table 1.

XRD analysis of GO sheet.

2θ (°)	10.50°	24.69°	27.10°
hkl (plane)	(0 1 1)	(0 0 2)	(0 0 2)

The spectra of FT-IR of as-synthesized GO powder (Figure 3) indicates a broad and strong peak at 3406 cm⁻¹ which corresponds to the C-OH group and an intercalated water molecules into the graphene oxide. The hydrogen bonds between carboxyl and hydroxyl groups may be the consequence of the effect of broadening which ranges from 3500 to 2000 cm⁻¹, typically the observed peak at 2890 cm⁻¹, (CH₂-group). Additionally, the functionalities of C-O bonds at 1045 cm⁻¹ (RCO-group), 1628 cm⁻¹ (COOH-group) and 1400 cm⁻¹ (-COO-group) clearly are visible. The spectrum also demonstrates a peak at 1729 cm⁻¹ (-C = O group), upon which oxidation of the graphite has been raised.²⁹ The various functional groups are given in Table 2.

Figure 3.

Spectra of Raman for (a) Pure GO, (b) EPD-GO coated copper pipe.

Table 2.

IR frequencies of GO sheet.

IR frequencies, cm⁻¹
Functional group	Wavenumber (cm⁻¹)
C-OH	3406
CH₂	2890
C-N	1045
COOH	1628
-COO	1400
-C = O	1729

Figure 3 illustrates the Raman spectra of both graphene oxide (GO) and the GO-coated copper pipe. Each spectrum exhibited two prominent characteristic peaks: the D band around 1350 cm-1 and the G band approximately at 1583 cm-1. The D band corresponds to the phonon breathing mode at the κ-point of A1g symmetry, while the G band primarily signifies the E_2g phonons of C Sp2 atoms.^30,31 The presence of various defects, edges, and groups in graphene leads to disorder, contributing to the intensity of the D peak. Higher degrees of disorder typically result in a stronger D peak. Additionally, the F peak plays a significant role in indicating the level of graphene’s reduction. Interestingly, the absence of the band 2D suggests a certain degree of graphitization missing from these spectra.

The ratio of peak intensities between F and E bands (ID/IG) inversely correlates with the size of the graphene sp2 zones, often serving as a characterization parameter for graphene’s defect level. The calculation from the spectra revealed an increase in the IF/IE ratio, ranging from 0.96 to 1.08, for both GO and the GO-coated copper pipe. This suggests the presence of localized sp3 defects within the carbon sp2 network resulting from GO reduction. However, despite these observations, the findings indicate that the EPD-GO process might not be solely responsible and could potentially be accompanied by an electrochemical reduction process.

The image of TEM was utilized to assess the structural features and the morphology of the GO produced. Generically, Figure 4 demonstrates that the GO produced has a morphology of nanosheet which agglomerate forming multilayer aggregates. The image clarifies vividly that graphene oxide had a quintessential structure (2D) of grooved morphology. Dark spots indicate GO’s multilayer, whiles layers of lower density results in the exfoliated nanostructure highlighted via the areas of transparency. Moreover, the image also shows the transparency number of sheets higher than the dark spots showing most layers of GO been well exfoliated.

Figure 4.

TEM image of graphene oxide (GO).

The spectra of UV of the EPD-GO Cu pipe’s deposition processes are shown in Figure 5. The GO suspension utilized as an electrolyte for the EPD process, the peak at 234 nm in the UV spectrum of the GO corresponds to π-π* transition of the sp² C = C bonds.³² After the EPD process, the peak of the absorption redshifted to 340 nm after GO reduction to graphene. This increased the π-conjugation restoring conjugation network.³³ As the π-conjugation increases, it requires less energy for such transition, corresponding to the shift observed in the absorption to the region of longer wavelength. Considering the edges and surfaces carrying significant amount of functional groups of oxygen, GO was successfully dispersed in the water as electrolyte which produced a yellowish-brown stable solution. Thus, EPD-GO coated Cu pipe surfaces were dark brown with few aggregated particles. This redshift showed electrochemical elimination of unstable functional groups of oxygen after EPD.

Figure 5.

UV/Vis spectra of (a) Graphite, (b) GO, (c) EPD-GO coated cu pipe.

The bonding strength between the copper pipe and graphene is intricately tied to the stretching dynamics between the copper surface and the carbon atom’s surface configurations, dictated by their unique surfaces. Illustrated in Figure 6 is the adhesion force observed in the EPD-prepared GO-coating. With a gradual increment in load from 0 to 4.6 N, the friction force exhibited a steady, incremental ascent characterized by a constant slope.³⁴ Upon reaching 4.6 N, a notable, abrupt escalation in friction force occurred, indicating a shift in the contact condition between the coating and the indenter. This change was visibly marked by a distinct spot observed on the surface of the GO-coated copper pipe, discernible to the naked eye. The adhesion strength was determined based on this observed spot’s appearance on the metal surface, signifying the coating’s adhesion.

Figure 6.

The adhesion force of GO coating prepared by EPD.

After exceeding the 4.6 N load, almost all surface abrasions on the coating vanished, indicating a significant compromise in the coating’s adhesion. Particularly noteworthy was the role played by the adhesion force between the coating and the substrate’s surface in bolstering the coating’s corrosion resistance. More precisely, the carboxyl groups located at the coating’s periphery established covalent bonds with the hydroxyl groups on the surface of the copper pipe post pretreatment, markedly amplifying the adhesion force beyond mere physical adherence.

The investigation into the morphology and composition of graphene oxide (GO) applied onto copper was conducted using scanning electron microscopy (SEM). Displayed in Figure 7(a) is the SEM depiction illustrating the bare copper surface. In contrast, Figure 7(c) showcases a distinctly uniform and exceedingly thin layer of GO sheets coating the copper substrate. The transparency of this layer is such that it allows the passage of an electron beam through the sample. Figure 7(d) shows an imaging of the copper pipe that was coated by GO through EPD technique, which shows that the GO coating forms a consistent and continuous film across the surface of the copper pipe. Besides, the graphene oxide coating contributed to a less rough surface texture compared to the bare copper pipe in Figure 7(a). The SEM images depict minor irregularities resulting from the presence of the graphene oxide layer. This analysis reveals improved coverage of the copper pipe surface by the graphene oxide coating, indicating a successful and uniform deposition process. Notably, the graphene oxide coating exhibits a tightly adhering nature to the copper substrate, indicating a well-defined and interconnected three-dimensional network of graphene sheets as shown in Figure 7(b). This structure resembles a porous arrangement akin to a loosely structured sponge, implying a cohesive and integrated morphology of the GO coating on the copper substrate. Examining the scratch morphology through field emission scanning electron microscopy (FESEM), as shown in Figure 8, revealed that the peeling zone of the coating was confined within the scratch, displaying characteristic spalling and buckling phenomena. As load and pressure increased, fractures and cracks emerged at points of maximum tensile stress, with crack propagation accelerating at the point of failure, indicating a sudden loss of adhesion in the coating. The coefficient of friction decreased from an initial value of approximately 0.6 before failure to around 0.3 after failure, reflecting reduced surface resistance as cohesion weakened post-failure.

Figure 7.

SEM images of (a) bare copper pipe, (b) GO coating, (c) EPD-GO coated Cu, and (d) EPD-GO coated Cu pipe.

Figure 8.

FESEM morphology of GO coating after scratch test.

Zeta potential is part of the important characteristics which influence the quality of the deposited film and its morphological structures in the EPD, notwithstanding its kinetics. Zeta potential is homologous to mobility via equation (1).

ξ = \frac{η μ}{ε ε °}

(1)

where

η

is the solution viscosity,

ζ

the zeta potential,

μ

is the particle mobility inside the solution,

ε

is the permittivity of the solution,

ε °

vacuum permittivity. It can be observed from the equation that the particles mobility is dependent on the,

ζ

potential, and increment in

ζ

potential, mobility of particles, as well as the solution stability increased.²⁶ Formation of agglomerates in the suspension is as a result of low value of

ζ

potential therefore less or no coating would be formed on the conducting substrate, or the formed coating will be less uniform and adhesive. However, in a situation of extremely high value of

ζ

potential, overcoming the force of repulsion between the particles by the electric field becomes problematic, thus coatings cannot be formed. The potential measured from de-ionized water was −62.50 mV as shown in Figure 9. In general, zeta potential changes in proportion to the degree of oxidation of graphene oxide to – 70 mV in inorganic solution. Negative

ζ

potential value indicates EPD on the anode and vice versa. The negatively charged functional groups on the GO surface could react with water which leads to release of H⁺ resulting in the suspension been acidic. According to colloidal chemistry, H⁺ ions are stationed around the GO sheets with negatively charged which neutralizes the overall charges of the system.²² Considering the measured value of the zeta potential, and via various experiments, 20 V for 60 s was selected for this study. Each experiment was repeated three times.

Figure 9.

Zeta potential dispersion analysis of graphene oxide suspended in aqueous solution.

Synthesis and analysis of coatings through electrophoretic deposition techniques

Electrophoretic deposition (EPD) was employed to achieve a uniform application of graphene oxide (GO) as both thick and thin films onto copper pipes. In an aqueous environment, the GO sheets acquired a negative charge, indicated by a zeta potential value of −62.50 mV. Consequently, during the EPD process, these negatively charged GO sheets moved towards the positive electrode. Electrolysis provides both beneficial and challenging roles during EPD as it assists in GO reduction which improves electrical conductivity, thereby enhancing adhesion. However, it also influences coating uniformity and also affects stability. To address this issue, prior to the electrophoretic deposition (EPD) process, the colloidal suspension was thoroughly degassed under reduced pressure to remove dissolved gases that could lead to bubble formation.

Upon the application of voltage (low voltages; between 3 and 10 V), electrolysis of water occurred, releasing oxygen molecules at the anode’s surface. The functional groups like carbonyl and carboxylate (RCOO⁻) present on the GO platelets interacted with the produced H⁺ ions from water dissociation, leading to their deposition onto the anode’s surface. Simultaneously, partial dissolution of the metal occurred, releasing metal ions (Mn⁺) that interacted with RCOO⁻, also depositing onto the anode’s surface. This interaction might contribute to a reduction in the adhesion of the GO layer on the copper pipe.

Research suggests that once an electronic connection is established at the anode, electrons migrate away from the GO platelets, triggering the oxidation of more carboxylic groups.³⁵ Consequently, unpaired electrons within the GO framework migrate freely, seeking other unpaired electrons to form covalent bonds. The presence of remnant carbonyl groups observed in the FT-IR results Figure 10 supports this mechanism. However, while this reaction may account for the loss of carboxylates, it fails to fully explain the reduction of oxygen atoms in GO.

Figure 10.

FT-IR spectra for, (a) graphite oxide, and (b) EPD-GO coated on cu pipe.

This reaction mechanism might be applicable for depositing GO in a bath without additives. Despite offering insight into the process, it does not entirely clarify the reduction of oxygen atoms within GO (GO reduction) or the specific role of certain chemical additives in this deposition process.

GO film on the copper pipe

The Figure 1(e) shown indicates the images of the layers of GO-EPD formed on copper pipe with different parameters. The film formed on the substrate cannot be easily peeled off by a simple tape test due to homogeneity and uniformity. Under the conditions of the used parameters such as low voltages and short time of deposition, the colour (brown) of the deposit reflects pristine conjugated domains of graphene oxide ³⁶ with the colour changing from brown to black when applied voltage was increased due to increase in film thickness and time.^36,37

Corrosion analyses

Figure 11 presents the electrochemical impedance spectroscopy (EIS) measurement in the form of Bode plots for both the bare copper pipe and the graphene oxide (GO)-coated copper pipe. The comparison between the two plots reveals that the GO-coated copper pipe exhibits a larger phase angle and impedance magnitude across a wide frequency range compared to the bare copper pipe. This increased impedance and phase shift suggest enhanced corrosion resistance provided by the GO coating. The larger impedance magnitude is indicative of an effective barrier that slows ion diffusion and inhibits electrochemical reactions responsible for corrosion. Consequently, the GO-coated pipe demonstrates superior corrosion protection, resulting in a lower corrosion rate relative to the uncoated copper pipe. These findings are consistent with similar studies in the literature, where coatings integrated with GO and other nanomaterials have significantly improved corrosion resistance. For instance, sol-gel modified films with GO, polyvinyl alcohol/graphene nanocomposites, and graphene/polyaniline composites have all demonstrated similar trends in corrosion protection by increasing impedance and acting as robust physical barriers.^38,39,40

Figure 11.

Electrochemical measurement of Bode plot for the corrosion of (Blue) bare copper pipe, (Orange) GO-coated Cu pipe in 0.5 M NaCl.

The Electrochemical Impedance Spectroscopy (EIS) results of the Nyquist plots for both the bare and GO-coated copper pipes were best represented by an equivalent circuit model as seen in Figure 12. This model comprised parameters such as the resistance (R_s) of the electrolyte solution, charge transfer resistance of the corrosion reaction (R_c), Warburg impedance (Y_o), and capacitance (C_dl), linked to the copper pipe’s O₂ diffusion. Notably, this model differed from a previous study ⁴¹ that proposed a two-layer oxide film representation, featuring an inner layer as a barrier-like structure and an outer porous layer. Since the GO deposition in this study was directly on the copper pipe, the model used here was distinct.

Figure 12.

Electrochemical measurement of Nyquist plot for corrosion of copper pipe with protective coating in 0.5 M NaCl.

The Bode plots demonstrated the absolute value of impedance against the phase shift, represented in Figure 11. They showed a less pronounced change in frequency, emphasizing the measurement of solution resistance. The EIS parameters for both the bare copper pipe and the EPD-GO coated copper pipe are summarized in Table 3.

Table 3.

The parameters of EIS of the bare copper pipe and EPD-GO coated copper pipe.

Sample	$R_{s}$ ( Ω )	$R_{c t} (Ω)$	$C_{d l} (μ F)$	$Y_{o} (μ M h o)$
Bare Cu pipe	15.98	16.34	35.96	8.17
EPD-GO coated Cu	16.49	−5.99	26.49	15.46

The corrosion mechanism of Cu is oxidation at the anode which occurs at the working electrode alongside the process of reduction in the cathode utilizing released of the electrons during Cu’s oxidation. Various cathodic and anodic reactions which occurs on the Cu electrode is given below:

C u \Rightarrow {C u}^{2 +} + {2 e}^{-}

(2)

Other reaction might occur during the process in the NaCl solution

C u + {2 C l}^{-} ⟹ {C u C l}^{- 2} + {2 e}^{-}

(3)

On the surface of the cathode, occurrence of reduction reaction via which electrolyte (such as $H^{+}$ and O₂) is reduced, with electron elimination from Cu considering the reaction:

{2 H}^{+} + {2 e}^{-} ⟹ H_{2}

(4)

O_{2} + 2 H_{2} O + {4 e}^{-} ⟹ {4 O H}^{-}

(5)

In the context of corrosion, the electron transfer occurring at the metal surface is greatly influenced by the reaction kinetics of both the cathodic and anodic reactions. As per this assumption, the corrosion rate (CR) that transpires between the cathode and anode is predominantly controlled by equilibrium. In this equilibrium state, no net current is observed as the reaction reaches an equilibrium state.⁴²

According to a study,⁴³ the flattened capacitive semi-circle and circle’s sector shows dispersion of frequency because of phosphate covering defects.⁴⁴ However, the EIS data indicates that the statement is true but for only corrosion process under neutral media. The diameter of the semi-circle increased until it reached maximum at which the GO content could not further increases. The larger the size of semicircle, the higher the resistance of polarization.⁴⁵ The Bode plots presented in Figure 11 align with the observations from the Nyquist plots in Figure 12, showcasing a similar trend in the changing impedance values |Z|.

The negative phase angle (-θ) observed at higher frequencies holds significance in evaluating the integrity of a coating when exposed to a corrosive electrolyte.⁴⁶ Specifically, the θ value at 10 kHz is recognized as indicative of the coating’s condition when subjected to such an environment. An intact coating with no defects typically exhibits a θ around −90°, while for uncoated steel, the θ approaches zero.⁴⁷ As depicted in Figure 11, the presence of a high θ at higher frequency ranges (10 kHz) correlates with superior corrosion protection characteristics. This suggests that the coating possesses higher density with fewer defects, a conclusion supported by the low corrosion rate (1.03 × 10-6 mm/yr.) and high corrosion efficiency (90.48%) observed in the assessment.

The Nyquist plot in Figure 12 includes a Randles-modified equivalent circuit, which consists of two key components: (Ro), representing the uncompensated resistance of the electrolyte solution, and (Rt), which corresponds to the polarization resistance. Here, instead of using ideal layer of double capacitor (C_dl), an element of constant phase (CPE_dl) was utilized to simulate accurately the characteristic frequency of distribution,⁴⁸ including Warburg (W) element, corresponding to the resistance of diffusion. CPE contains ratio of impedance dispersion, $= \frac{1}{Y_{o} {(f w)}^{n}}$ , where n and Y_o are the index of empirical CPE and conductivity, respectively, w is angular frequency, and f is an arbitrary number.⁴⁹ The resulting curves exhibit a capacitive loop at higher frequencies, running parallel to double-layer capacitance, alongside a gentle tail observed at lower frequencies. This latter portion is presumed to represent a diffusion process, characterized by a smoothed tail explained by W, as established in a prior study.⁵⁰

By utilizing the Tafel method of extrapolation at the convergence of anodic and cathodic polarization curves, various electrochemical parameters were derived. These parameters include corrosion current density (i_corr), corrosion potential (E_corr), corrosion rate (CR), equivalent weight (EW) of the copper pipe, resistance efficiency, and η values for both the bare copper pipe and the EPD-GO coated copper pipe. These parameters were extrapolated employing specific equations standardized for such analyses. ASTM G102 – 89⁵¹:

C o r r o s i o n r a t e (C R) = K \frac{i_{c o r r}}{ρ} E W

(6)

E q u i v a l e n t w a i t (E W) = \frac{1}{\sum \frac{n i f i}{W i}}

(7)

R e s i s t a n c e e f f i c i e n c y (η) = \frac{i_{c o r r} (b a r e) - i_{c o r r} (c o a t i n g)}{i_{c o r r} (b a r e)} 100 %

(8)

Here, i_corr represents the corrosion current density, while K denotes the constant defining the corrosion rate (3.27 × 10-3 mm g/μA cm year). Additionally, EW stands for the equivalent weight (31.70 g), and ρ signifies the density of the copper pipe (8.9 g/cm³). The parameters f_i, W_i, and Ni represent the mass fraction, atomic weight, and valence, respectively, of the i^th element within the alloy or coating.

Furthermore, the passive current density (i_p) was determined by measuring midway between E_pit and E_corr. It’s noteworthy that all measurements were conducted three times to ensure accuracy and reliability. Additionally, the surface of some specimens was examined after the electrochemical testing to further analyze their condition and characteristics.

The EPD-GO coated copper pipe restricted either the oxidation at the anode or prevented the OH⁻ ions contact. It is highly practical to inhibit copper pipe’s corrosion. Aside that, adequate O₂ and H₂O are required for the corrosion to occur and copper pipe’s dissolution.⁵² Consequently, EPD-GO coatings play a significant role in adding to the pathway of O₂ and H₂O molecules dissolution to the copper pipe. Figure 13 exhibits the Open Circuit Potential (OCP) measurements of both the bare copper and EPD-GO coated Cu pipes in a 3.5 wt% NaCl solution. Initially, the EPD-GO coated Cu pipe showed a significant reduction in potential, transitioning from 138 mV to −33 mV within 600 s. Subsequently, it gradually stabilized, reaching −51 mV after 1600 s. In comparison, the bare Cu pipe started at −118 mV and experienced a slight decrease to −169 mV after 600 s, stabilizing at −174 mV after 1600 s. The EPD-GO coated Cu pipe displayed a notably higher positive OCP (−49.8 mV) in contrast to the bare Cu pipe (−174.5 mV). This difference indicates that the application of the GO coating significantly reduces the corrosion rate (CR) of the Cu pipe.^53,54 The corrosion current density ( $i_{c o r r}$ ) and corrosion potential ( $E_{c o r r}$ ) are the parameters utilized to extrapolate the resistance the coatings offered against corrosion obtained from interception of the Tafel slopes. The bare copper pipe’s polarization potential curves and the coated copper pipe that are presented in Figure 14 demonstrate that EPD-GO coatings changed the cathodic process reduction reaction of O₂. The remarkable properties of the EPD-GO layers include their strong barrier characteristics and high crosslinking density, which effectively reduce the active available surface area susceptible to attack by the corrosive medium. This impedes the reduction reaction of O2. Additionally, the electrical conductivity of GO contributes to reducing the active surface resistance. The results from the Potentiodynamic polarization analysis of both the bare copper pipe and the EPD-GO coated substrates are summarized in Table 4. The corrosion potential (E_corr) serves as an indicator of surface stability in the corrosive environment. Notably, the EPD-GO coatings exhibited a positive shift in E_corr compared to the bare copper pipe, signifying enhanced stability against corrosion compared to the bare pipe. This improvement in corrosion resistance could be attributed to the barrier properties and functional groups present on the edges and basal planes of GO. This aligns with findings from other studies,^62–64 which demonstrated that nanosheets enhance mechanical properties and corrosion resistance in various fibrous and particulate compositions due to their electrical conductivity.

Figure 13.

Open Circuit Potential for (a) Bare copper pipe, (b) EPD-GO coated copper pipe.

Figure 14.

Tafel polarization curve of (a) bare copper, (b) GO-coated copper pipe.

Table 4.

Comparative assessment for Tafel curve parameters for bare copper pipe and EPD-GO coated copper.

Sample	i_corr	E_corr	CR	E_pit	i_p	η
Sample	(Acm-²)	(V vs SCE)	(mm/yr.)	(mV)	(µAcm-²)	(%)
Bare Cu pipe	0.168 × 10⁻⁶	−0.171	16.16 × 10⁻⁶	0.214	0.626	—	Current study
EPD-GO coated	0.016 × 10⁻⁶	0.032	1.03 × 10⁻⁶	0.219	0.055	90.48	Current study
Bare copper	—	−235.3	0.18	—	15.375	19.08	⁵⁵
Bare copper	—	−211	0.289	−173.3	25	-	⁵⁶
GO coated copper	—	−182.2	0.15	—	12.44	-	³¹
GO coated on copper	—	−195	0.147	−50.4	12.7	49.2	³³
Bare copper	—	418.9	2.489	−154	21.54	-	⁵⁷
Single layer GO/CU	—	325.2	0.867	−149	7.504	65.16	⁵⁷
Double layer GO/CU	—	251.8	0.554	−142	4.796	77.73	⁵⁷
Bare copper	—	−289	0.00757	—	—	—	⁵⁸
In-plane Graphebe/CU	—	−209	—	—	—	88.3	⁵⁸
Few layers of Graphene/CU	—	−125	0.00914	—	—	98.7	⁵⁸
Bare copper	—	−285.2	—	—	2.38	—	⁵⁹
Copper +0.8% GO	—	−229.3	—	—	1.25	—	⁵⁹
Copper +2.4% GO	—	−249.2	—	—	1.48	—	⁵⁹
Bare copper	—	−211.3	0.5499	—	47.41	65.5%	⁶⁰
Copper coated GO	—	−155.3	0.1850	—	15.95	66.3%	⁶⁰
Bare copper	−270	—	0.076	—	6.5	—	⁶¹
Copper +2% GO	−340	—	0.016	—	1.4	—	⁶¹
Copper +4% GO	−430	—	0.003	—	0.34	—	⁶¹

Moreover, the observed passive current density (I_p) values in Table 4 indicate the applied potential for both bare copper pipe and EPD-GO coated copper pipe. Both substrates displayed lower values of I_p, indicating the formation of highly stable passive films on the copper pipe’s surface. This stability further contributes to their improved corrosion resistance. This evidence supports the protective corrosion barrier of EPD-GO coating as previously mentioned. In summary, the comparative assessment of Tafel curve parameters between bare copper and EPD-GO coated copper provides valuable insights into the electrochemical behaviors, corrosion resistance, reaction kinetics, catalytic activities, and stability of these materials in various electrochemical applications.

In addition, bare copper pipe’s corrosion rate was recorded as 1.616 × 10⁻⁵ mm/yr, whiles that of the EPD-GO coated copper pipe was 1.03 × 10⁻⁵ mm/yr. The corrosion rate value obtained for the bare copper pipe lies between results obtained by Zhang et al,⁶⁵ that is, 2.4 × 10⁻⁴ mm/yr and Chembath et al,⁶⁶ that is, 6.98 × 10⁻⁶ mm/yr. Additionally, it was found out by Zhang that EPD-GO coated corrosion resistance to be 1.4 × 10⁻⁴ mm/yr but unlike ours, the corrosion resistance (1.03 × 10⁻⁵ mm/yr) was better than theirs. This might be because of low voltage utilization (10 V) in their work than ours which is 25 V for EPD-GO coating. Additionally, the hypercritical potential happens to be the pitting potential ( $E_{p i t}$ ), that is pitting nucleation begins. The change in the behaviour of corrosion was seen vividly for the bare copper pipe at 0.214 mV (Table 4) but EPD-GO coated copper pipe demonstrated most pitting potential. The value of the pitting potential was 0.219 V for the EPD-GO coated copper pipe. This shows that EPD-GO coated copper pipe presented higher protection to the pitting corrosion compared to the bare copper pipe. Finally, the resistance efficiency (η) in our work recorded as 90.48 % for the EPD-GO coatings.^{67,68,69,70,71,72,73,74,75,76,77,78,79,80}

Conclusion

Utilizing the Electrophoretic Deposition (EPD) method, a copper pipe underwent a uniform coating process with a fine layer of graphene oxide (GO) nanosheets, sourced from a stable aqueous colloidal suspension. The suspension’s stability was verified through zeta potential measurement, yielding a value of −28.9 mV. Ideal parameters were established to achieve a well-bonded deposit on the Cu pipe: employing a suspension concentration of 0.5 mg/mL alongside an applied potential of 20 V for 60 s. Examination via SEM imaging unveiled a deposited layer measuring 2.23 μm in thickness. Evaluation through XRD, FT-IR, and the C/O weight ratio confirmed the reduction of GO throughout the EPD process.

Electrochemical corrosion tests showcased the superiority of the EPD-GO coated copper pipe. It exhibited increased impedance, higher resistance efficiency, and notably lower corrosion rate (CR) values compared to the uncoated copper pipe. Moreover, the GO coating functioned as a barrier, preventing charge exchange between the Cu pipe and its surrounding environment while remaining inert to other substances. This significantly bolstered the Cu pipe’s protection, especially when subjected to testing in a 3.5% NaCl solution. The application of GO treatment using EPD deposition demonstrates promising potential for utilizing Cu pipes in severe corrosive industrial settings.

Abbreviations

Copper

H2O2

Hydrogen Peroxide

CVD

Chemical Vapor Deposition

H2SO4

Sulfuric Acid

EIS

Electrochemical Impedance

HCl

Hydrochloric Acid

EPD

Electrochemical Deposition

HNO3

Nitric Acid

FESEM

Field Emission Scanning Electron Microscopy

KMnO4

Potassium Permanganate

FT-IR

Fourier Transform Infrared Spectroscopy

OCP

Open Circuit Potential

Graphite

SEM

Scanning Electron Microscopy

Graphene Oxide

SiC

Silicon Carbide

SiO2

Silicon Oxide

TEM

Transmission Electron Microscopy

XRD

X-ray Diffraction

Footnotes

Acknowledgments

The authors extend their appreciation to the Japan International Cooperation Agency (JICA) for their gracious financial backing, and to the Egypt-Japan University of Science and Technology (E-JUST) for their indispensable technical guidance.

Author contributions

M. M. Y. Z., Conceptualization, Methodology, Resources, Formal analysis, Investigation, Visualization, Writing - original draft, Writing - review & editing, Supervision. M. F., Conceptualization, Methodology, Resources, Writing - original draft, Writing - review & editing. D. A., Writing - review & editing. M. M. Y. Z., Conceptualization, Methodology, Resources, Formal analysis, Writing - review & editing.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Moustafa M. Yousry Zaghloul

Data availability statement

Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.*

References

Rahmanto

Gunawam

. Corrosion rate of copper and iron in seawater based on resistance measurement. J Coast Dev 2002; 5(2): 1410–5217.

Fuseini

Zaghloul

MMY

Elkady

, et al. Evaluation of synthesized polyaniline nanofibres as corrosion protection film coating on copper substrate by electrophoretic deposition. J Mater Sci 2022; 57(10): 6085–6101. DOI: 10.1007/s10853-022-06994-3.

Zaghloul

MMY

Zaghloul

MMY

Fuseini

. Recent progress in Epoxy Nanocomposites: corrosion, structural, fame retardancy and applications — a comprehensive review. Polym Adv Technol 2023; 34(18): 6144. DOI: 10.1002/pat.6144.

Mahmoud Zaghloul

Yousry Zaghloul

. Physical analysis and statistical investigation of tensile and fatigue behaviors of glass fiberreinforced polyester via novel fibers arrangement. J Compos Mater 2023; 57(1): 147–166. DOI: 10.1177/00219983221141154.

Zaghloul

MMY

. Efect of nano particles on the mechanical properties of thermosetting polymeric materials reinforced with glass fibers, MSc Thesis. Egypt: Faculty of Engineering, Alexandria University, 2018.

Fuseini

Zaghloul

MMY

. Investigation of electrophoretic deposition of PANI nano fibers as a manufacturing technology for corrosion protection. Prog Org Coating 2022; 171: 107015. DOI: 10.1016/j.porgcoat.2022.107015.

Sanjinés

Abad

Vâju

, et al. Electrical properties and applications of carbon based nanocomposite materials: an overview. Surf Coat Technol 2011; 206(4): 727–733. DOI: 10.1016/j.surfcoat.2011.01.025.

Dikin

Stankovich

Zimney

, et al. Preparation and characterization of graphene oxide paper. Nature. 2007; 448(7152): 457–460. doi:10.1038/nature06016.

Narula

Tan

. Determining the parameters of importance of a graphene synthesis process using design-of-experiments method. Appl Sci 2016; 6(7): 204. DOI: 10.3390/app6070204.

10.

Tung

Allen

Yang

, et al. High-throughput solution processing of large-scale graphene. Nat Nanotechnol 2009; 4(1): 25–29. DOI: 10.1038/nnano.2008.329.

11.

Z-S

Pei

Ren

, et al. Field emission of single-layer graphene films prepared by electrophoretic deposition. Adv Mater 2009; 21(17): 1756–1760. DOI: 10.1002/adma.200802560.

12.

Singh Raman

Chakraborty Banerjee

Lobo

, et al. Protecting copper from electrochemical degradation by graphene coating. Carbon N Y 2012; 50(11): 4040–4045. DOI: 10.1016/j.carbon.2012.04.048.

13.

Kang

Kwon

Cho

, et al. Oxidation resistance of iron and copper foils coated with reduced graphene oxide multilayers. ACS Nano 2012; 6(9): 7763–7769. DOI: 10.1021/nn3017316.

14.

Kirkland

Schiller

Medhekar

, et al. Exploring graphene as a corrosion protection barrier. Corrosion Sci 2012; 56: 1–4. DOI: 10.1016/j.corsci.2011.12.003.

15.

Raza

Rehman

Ghauri

, et al. Corrosion study of electrophoretically deposited graphene oxide coatings on copper metal. Thin Solid Films 2016; 620: 150–159. DOI: 10.1016/j.tsf.2016.09.036.

16.

Singh

Jena

Bhattacharjee

, et al. Development of oxidation and corrosion resistance hydrophobic graphene oxide-polymer composite coating on copper. Surf Coat Technol 2013; 232: 475–481. DOI: 10.1016/j.surfcoat.2013.06.004.

17.

Geckle

Mroczkowski

. Corrosion of precious due to mixed metal flowing plated copper gas exposure alloys. Journal of Reinforced Plastics and Composites. 2000; 14(I): 162–169.

18.

Honor

Presented

, Graphene oxidation barrier coating xu zhou 2011.

19.

Besra

Liu

. A review on fundamentals and applications of electrophoretic deposition (EPD). Prog Mater Sci 2007; 52(1): 1–61. DOI: 10.1016/j.pmatsci.2006.07.001.

20.

Besra

Uchikoshi

Suzuki

, et al. Bubble-free aqueous electrophoretic deposition (EPD) by pulse-potential application. J Am Ceram Soc 2008; 91(10): 3154–3159. DOI: 10.1111/j.1551-2916.2008.02591.x.

21.

Ferrari

Moreno

. Electrophoretic deposition of aqueous alumina slips. J Eur Ceram Soc 1997; 17(4): 549–556. DOI: 10.1016/S0955-2219(96)00113-6.

22.

Shao

Wang

Engelhard

, et al. Facile and controllable electrochemical reduction of graphene oxide and its applications. J Mater Chem 2010; 20(4): 743–748. DOI: 10.1039/b917975e.

23.

Diba

García-Gallastegui

Klupp Taylor

, et al. Quantitative evaluation of electrophoretic deposition kinetics of graphene oxide. Carbon N Y 2014; 67: 656–661. DOI: 10.1016/j.carbon.2013.10.041.

24.

Wang

Park

, et al. Synthesis of enhanced hydrophilic and hydrophobic graphene oxide nanosheets by a solvothermal method. Carbon N Y 2009; 47(1): 68–72. DOI: 10.1016/j.carbon.2008.09.002.

25.

Miletić

Terek

Kovačević

, et al. Influence of substrate roughness on adhesion of TiN coatings. J Braz Soc Mech Sci Eng 2014; 36(2): 293–299. DOI: 10.1007/S40430-013-0102-2/METRICS.

26.

Zaghloul

MMY

Steel

Veidt

, et al. Wear behaviour of polymeric materials reinforced with manmade fibres: a comprehensive review about fibre volume fraction influence on wear performance. J Reinforc Plast Compos 2021; 41: 215–241. DOI: 10.1177/07316844211051733.

27.

Zaghloul

MMY

Steel

Veidt

, et al. Mechanical and tribological performances of thermoplastic polymers reinforced with glass fibres at variable fibre volume fractions. Polymers 2023; 15: 694. DOI: 10.3390/polym15030694.

28.

Zaghloul

MMY

Steel

Veidt

, et al. Influence of counter-face grit size and lubricant on the abrasive wear behaviour of thermoplastic polymers reinforced with glass fibres. Tribol Lett 2023; 71: 102. DOI: 10.1007/s11249-023-01774-9.

29.

Zaghloul

MMY

Zaghloul

MYM

Zaghloul

MMY

. Experimental and modeling analysis of mechanical-electrical behaviors of polypropylene composites filled with graphite and MWCNT fillers. Polym Test 2017; 63: 467–474. DOI: 10.1016/j.polymertesting.2017.09.009.

30.

Ferrari

Robertson

. Interpretation of Raman spectra of disordered and amorphous carbon. Phys Rev B 2000; 61(20): 14095–14107. DOI: 10.1103/PhysRevB.61.14095.

31.

Fuseini

Zaghloul

MMY

. Statistical and qualitative analyses of the kinetic models using electrophoretic deposition of polyaniline. J Ind Eng Chem 2022; 113: 475–487. DOI: 10.1016/j.jiec.2022.06.023.

32.

Lih

ETY

Zaid

Tan

, et al. Facile corrosion protection coating from graphene. Int. J. Chem. Eng. Appl 2012: 453–455. DOI: 10.7763/IJCEA.2012.V3.242.

33.

Gurunathan

Han

Kim

, et al. Reduction of graphene oxide by resveratrol: a novel and simple biological method for the synthesis of an effective anticancer nanotherapeutic molecule. Int J Nanomed 2015; 10: 2951–2969. DOI: 10.2147/IJN.S79879.

34.

Zaghloul

MMY

Steel

Veidt

, et al. Assessment of the tribological performance of glass fibre reinforced polyamide 6 under harsh abrasive environments. Tribol Int 2024; 191: 109059. DOI: 10.1016/j.triboint.2023.109059.

35.

Fritz

Lange

Giesbers

, et al. Simultaneous silicon oxide growth and electrophoretic deposition of graphene oxide. Langmuir 2019; 35: 3717–3723. DOI: 10.1021/ACS.LANGMUIR.8B03139.

36.

Sun

Pang

Cheng

, et al. Synthesis of wafer-scale graphene with chemical vapor deposition for electronic device applications. Adv Mater Technol 2021; 6(7): 2000744. DOI: 10.1002/ADMT.202000744.

37.

Bange

. Colouration of tungsten oxide films: a model for optically active coatings. Sol Energy Mater Sol Cells 1999; 58(1): 1–131. DOI: 10.1016/S0927-0248(98)00196-2.

38.

Mahmoud Zaghloul

Yousry Zaghloul

. Developments in polyester composite materials—an in-depth review on natural fibres and nano fillers. Compos Struct 2021; 278: 114698. DOI: 10.1016/j.compstruct.2021.114698.

39.

Mohamed

El-Gamal

Zaghloul

MMY

. Micro-hardness behavior of fiber reinforced thermosetting composites embedded with cellulose nanocrystals. Alex Eng J 2018; 57(4): 4113. DOI: 10.1016/j.aej.2018.10.012.

40.

Zaghloul

MMY

Mohamed

El-Gamal

. Fatigue and tensile behaviors of fiberreinforced thermosetting composites embedded with nanoparticles. J Compos Mater 2018; 53(6): 709–718. DOI: 10.1177/0021998318790093.

41.

Fuseini

Zaghloul

MMY

. Investigation of electrophoretic deposition of PANI nano fibers as a manufacturing technology for corrosion protection. Prog Org Coating 2022; 171: 107015. DOI: 10.1016/j.porgcoat.2022.107015.

42.

Sharma

Goyat

Vishwakarma

. Synthesis of Polymer Nano-composite coatings as corrosion inhibitors: a quick review. IOP Conf Ser Mater Sci Eng 2020; 983(1): 012016. DOI: 10.1088/1757-899X/983/1/012016.

43.

Jiang

Cheng

. Anti-corrosion zinc phosphate coating on building steel via a facile one-step brushing method. Electrochem Commun 2019; 109: 106596. DOI: 10.1016/j.elecom.2019.106596.

44.

Bagal

Kathavate

Deshpande

. Nano-TiO2 phosphate conversion coatings – a chemical approach. Electrochem Energy Technol 2018; 4(1): 47–54. DOI: 10.1515/EETECH-2018-0006/HTML.

45.

Zhou

Cong

, et al. Electrochemical techniques, impedance, and spectroscopy. Non-Destructive Eval 2018: 1–27. DOI: 10.1007/978-3-319-30050-4_7-1.

46.

Zhang

Wang

Zeng

, et al. Corrosion resistance and superhydrophobicity of one-step polypropylene coating on anodized AZ31 Mg alloy. J Magnesium Alloys 2021; 9(4): 1443–1457. DOI: 10.1016/j.jma.2020.06.011.

47.

Zhang

, et al. Corrosion and aging of organic aviation coatings: a review. Chin J Aeronaut 2023; 36(4): 1–35. DOI: 10.1016/j.cja.2022.12.003.

48.

Vyas

Wang

, “Electrochemical analysis of conducting polymer thin films,” Int J Mol Sci 2010, Vol. 11, Pages 1956-1972. DOI: 10.3390/IJMS11041956.

49.

Lin

. Self-healing performance of composite coatings prepared by phosphating and cerium nitrate post-sealing. J Wuhan Univ Technol -Materials Sci Ed 2015; 30(4): 813–817. DOI: 10.1007/S11595-015-1233-3.

50.

Arias

Barbosa Segundo

dos Santos

, et al. Direct Electro-oxidation of H2S gas in a membrane electrode assembly cell (MEA): a proof of concept. Sep Purif Technol 2023; 311: 123354. DOI: 10.1016/j.seppur.2023.123354.

51.

Manfredi

de Andrade Silva

. Test methods for the characterization of polypropylene fiber reinforced concrete: a comparative analysis. KSCE J Civ Eng 2020; 24(3): 856–866. DOI: 10.1007/S12205-020-0741-7.

52.

Chang

Huang

Peng

, et al. Novel anticorrosion coatings prepared from polyaniline/graphene composites. Carbon N Y 2012; 50(14): 5044–5051. DOI: 10.1016/j.carbon.2012.06.043.

53.

Anirudh

Krishnamurthy

Kandasubramanian

, et al. Probing into atomically thin layered nano-materials protective coating for aerospace and strategic defence application – a review. J Alloys Compd 2023; 968(Dec): 172203. DOI: 10.1016/j.jallcom.2023.172203.

54.

Aliofkhazraei

Macdonald

Matykina

, et al. Review of plasma electrolytic oxidation of titanium substrates: mechanism, properties, applications and limitations. Appl. Surf. Sci. Adv 2021; 5(Sep): 100121. DOI: 10.1016/j.apsadv.2021.100121.

55.

Usha Kiran

Dey

Singh

, et al. Graphene coating on copper by electrophoretic deposition for corrosion prevention. Coatings 2017; 7(12): 214. DOI: 10.3390/coatings7120214.

56.

Mohammed Ali Al-Sammarraie

Hasan Raheema

. Electrodeposited reduced graphene oxide films on stainless steel, copper, and aluminum for corrosion protection enhancement. Int. J. Corros 2017; 2017: 1–8. DOI: 10.1155/2017/6939354.

57.

Liu

Chen

, et al. The synthesis of graphene coated copper from PMMA and the anticorrosion performance of copper substrate. Mater Res Express 2020; 7(1): 016591. DOI: 10.1088/2053-1591/ab69bf.

58.

Zheng

Yang

Xian

, et al. In situ grown vertically oriented graphene coating on copper by plasma-enhanced CVD to form superhydrophobic surface and effectively protect corrosion. Nanomaterials 2022; 12(18): 3202. DOI: 10.3390/nano12183202.

59.

Wang

Luo

, et al. Ag-RGO content dependence of the mechanical, conductive and anti-corrosion properties of copper matrix composites. Mater Res Express 2018; 5(9): 096523. DOI: 10.1088/2053-1591/aad8e7 (Accessed 26 Dec. 2023).

60.

Mohammed Ali Al-Sammarraie

Hasan Raheema

. Electrodeposited reduced graphene oxide films on stainless steel, copper, and aluminum for corrosion protection enhancement. International Journal of Corrosion 2017; 2017: 1–8. DOI: 10.1155/2017/6939354.

61.

Krishnan

Aneja

Shaikh

, et al. Graphene-based anticorrosive coatings for copper. RSC Adv 2018; 8(1): 499–507. DOI: 10.1039/c7ra10167h.

62.

Zaghloul

MMY

Zaghloul

MMY

. Influence of stress level and fibre volume fraction on fatigue performance of glass fibre-reinforced polyester composites. Polymers 2022; 14(13): 2662. DOI: 10.3390/polym14132662.

63.

Zaghloul

MMYM

. Mechanical properties of linear low-density polyethylene fireretarded with melamine polyphosphate. J Appl Polym Sci 2018; 135(46): 46770. DOI: 10.1002/app.46770.

64.

Zaghloul

MMY

Zaghloul

MMY

. Influence of flame retardant magnesium hydroxide on the mechanical properties of high density polyethylene composites. J Reinforc Plast Compos 2017; 36(24): 1802–1816. DOI: 10.1177/0731684417727143.

65.

Zhang

Xiao

Zhang

, et al. The study on corrosion behavior and corrosion resistance of ultralow carbon high silicon iron-based alloy. Mater Res Express 2021; 8(2): 026504. DOI: 10.1088/2053-1591/ABDC52.

66.

Chembath

Balaraju

Sujata

. In vitro corrosion studies of surface modified NiTi alloy for biomedical applications. Adv Biomater 2014; 2014: 1–13. DOI: 10.1155/2014/697491.

67.

Zaghloul

MMY

Fuseini

Zaghloul

MMY

. Review of epoxy nano-filled hybrid nanocomposite coatings for tribological applications. FlatChem 2024; 100768. DOI: 10.1016/j.flatc.2024.100768.

68.

Zhang

Bai

, et al. Highly conducting graphene sheets and Langmuir-Blodgett films. Nat Nanotechnol 2008; 3(9): 538–542. DOI: 10.1038/nnano.2008.210.

69.

Zhu

Pan

, et al. Electrophoretic deposition of reduced graphene-carbon nanotubes composite films as counter electrodes of dye-sensitized solar cells. J Mater Chem 2011; 21(38): 14869–14875. DOI: 10.1039/c1jm12433a.

70.

Dong

Zeng

Lan

, et al. Field emission from few-layer graphene nanosheets produced by liquid phase exfoliation of graphite. J Nanosci Nanotechnol 2010; 10(8): 5051–5055. DOI: 10.1166/jnn.2010.2432.

71.

Eda

Emrah Unalan

Rupesinghe

, et al. Field emission from graphene based composite thin films. Appl Phys Lett 2008; 93(23): 1–4. DOI: 10.1063/1.3028339.

72.

Nethravathi

Rajamathi

. Chemically modified graphene sheets produced by the solvothermal reduction of colloidal dispersions of graphite oxide. Carbon N Y 2008; 46(14): 1994–1998. DOI: 10.1016/j.carbon.2008.08.013.

73.

Cheong

Zhitomirsky

. Electrodeposition of alginic acid and composite films. Colloids Surfaces A Physicochem. Eng. Asp 2008; 328(1–3): 73–78. DOI: 10.1016/j.colsurfa.2008.06.019.

74.

Cheong

Zhitomirsky

. Electrophoretic deposition of manganese oxide films. Surf Eng 2008; 25(5): 346–352. DOI: 10.1179/174329408x281786.

75.

Park

Kim

Park

. Electrophoretic deposition of nano-ceramics for the photo-generated cathodic corrosion protection of steel substrates. Surf Coat Technol 2013; 236: 172–181. DOI: 10.1016/j.surfcoat.2013.09.044.

76.

Diba

Fam

DWH

Boccaccini

, et al. Electrophoretic deposition of graphene-related materials: a review of the fundamentals. Progress in materials science. Pergamon: Elsevier, 2016, pp. 83–117. DOI: 10.1016/j.pmatsci.2016.03.002.

77.

Raza

Ali

Ghauri

, et al. Electrochemical behavior of graphene coatings deposited on copper metal by electrophoretic deposition and chemical vapor deposition. Surf Coat Technol 2017; 332(September): 112–119. DOI: 10.1016/j.surfcoat.2017.06.083.

78.

Zhu

Chen

, et al. Electrophoretic deposition of graphene oxide as a corrosion inhibitor for sintered NdFeB. Appl Surf Sci 2013; 279: 416–423. DOI: 10.1016/j.apsusc.2013.04.130.

79.

Park

. Electrophoretic deposition of graphene oxide on mild carbon steel for anti-corrosion application. Surf Coat Technol 2014; 254: 167–174. DOI: 10.1016/j.surfcoat.2014.06.007.

80.

Zhu

Lee

, et al. Thin film fabrication and simultaneous anodic reduction of deposited graphene oxide platelets by electrophoretic deposition. J Phys Chem Lett 2010; 1(8): 1259–1263. DOI: 10.1021/jz100080c.

Revolutionizing copper pipe durability: Shielding against corrosion with graphene oxide through electrophoretic application

Abstract

Keywords

Introduction

Experimental work

Materials and chemicals

Graphene oxide synthesis

Preparation of graphene oxide suspension

Sample preparation for electrophoretic deposition (EPD) of GO on Cu pipe

Characterization

Results and discussion

Synthesis and analysis of coatings through electrophoretic deposition techniques

GO film on the copper pipe

Corrosion analyses

Conclusion

Abbreviations

Footnotes

Acknowledgments

Author contributions

Declaration of conflicting interests

Funding

ORCID iD

Data availability statement

References