Influence of Graphene Oxide Content on the Zn-Gr Composite Layer Prepared by Pulse Reverse Electro-plating

Abstract

The Zinc (Zn)-graphene (Gr) composite layer was prepared successfully by using a pulse reverse electro-plating method on the iron substrate. Effect of GO content in the electrolyte on the microstructures of the composite layer and the corrosion behaviors in the 3.5 wt% NaCl solution were also investigated in detail by using scanning electron microscope (SEM), X-Ray Diffraction (XRD) and a series of electrochemical measurements. The results revealed that: 1) GO can be reduced into Gr during the co-deposition of electro-plating; 2) adding GO in the electrolyte changed the Zn growth mechanism in the composite layer, i.e., gradually transforming from the main preferred orientations of ( 112) and ( 101) crystal planes into ( 103), ( 102) and ( 110) planes 3) there is an optimal GO adding amount in a range 0.3-0.5g/L in the electrolyte, at which the Zn-Gr composite layer exhibited the highest corrosion resistance and corrosion current density just be a hundredth comparing with that of pure Zn layer in simulated seawater environment; 4) the Zn-Gr composite layer is of a strong adhesion with the substrate. The present work is expected to provide basic data for future practical applications in galvanized steel used for corrosion environment.

Graphene-Reinforced Zn–Ni Alloy Composite Coating on Iron Substrates by Pulsed Reverse Electrodeposition and Its High Corrosion Resistance

“…These results reveal three facts, that is, (1) the Gr sheets provided additional nucleation sites and resulted in small and dense grains, which changed the original homogeneous nucleation into heterogeneous nucleation during electrodeposition; (2) Gr also hindered the grain growth; (3) excessive GO sheets in the electrolyte decreased the content of the Gr-reinforcing phase in the coating due to agglomeration and poor dispersion and weakened the enhancement effect. In fact, the phenomenon of the “optimal Gr adding content” in the metal–Gr composites has been confirmed by many research studies. ,,, …”

“…It is well known that Zinc (Zn) and Zn-based alloy coatings, involving zinc–cobalt (Zn–Co), zinc–nickel (Zn–Ni), zinc–chromium (Zn–Cr), zinc–copper (Zn–Cu), and zinc–iron (Zn–Fe), provide economical ways to enhance the anti-corrosion performance of iron and steel, which has been employed in industry widely. − In recent years, in order to enhance the corrosion resistance of thin coatings in harsh environments, many composite coatings have been developed for meeting challenging applications. , As we all know, compared with their bulk materials, nano-sized materials have a significant large surface area to volume ratio and therefore, nanocomposite coatings have been widely explored for applications . Correspondingly, various nanomaterials have been used as reinforcing phases for preparing the composite coatings in the field of electrodeposition, such as zinc–nickel alloy–cerium oxide (Zn–Ni alloy–CeO 2 ), zinc–nickel alloy–aluminum oxide (Zn–Ni alloy–Al 2 O 3 ), zinc–nickel alloy–silicon nitride (Zn–Ni alloy–Si 3 N 4 ), zinc–titanium oxide (Zn–TiO 2 ), zinc–nickel–phosphorus alloy–silicon carbide (Zn–Ni–P alloy–SiC), nickel–phosphorus alloy–tungsten carbide (Ni–P alloy–WC), zinc–nickel alloy–carbon nanotubes (Zn–Ni alloy–CNTs), nickel–reduced graphene oxide (Ni–rGO), and zinc–graphene (Zn–Gr). − …”

“…Jabbar et al fabricated the Ni–Gr composite coatings on carbon steel at different deposition temperatures, and the results showed that the coating deposited at 45 °C exhibited a coarser surface morphology with increased carbon content, refined grain sizes, high micro hardness, and better corrosion resistance performance. In our previous work, the Cu–Gr composite coating via electroless plating and the Fe–Gr and Zn–Gr composite coatings via electrodeposition were prepared, which showed enhanced mechanical property and corrosion resistance. In addition, the Cu–Gr composite based upon high-quality graphene was also prepared via spark plasma sintering and exhibited better electrical conductivity …”

Graphene/Pyridylporphyrin Hybrids Interfacially Linked with Rare Earth Ions for Enhanced Photocatalytic Hydrogen Evolution

“…In addition, XRD of samples was performed to characterize the microstructures of the products with and without Sm 3+ . As shown in Figure B­(c), the peak at 2θ = 10.1° corresponds to the (001) facet of the GO . The interlayer spacing between GO sheets is about 8.8 Å according to the Bragg equation.…”

“…As shown in Figure 3B(c), the peak at 2θ = 10.1°corresponds to the (001) facet of the GO. 24 The interlayer spacing between GO sheets is about 8.8 Å according to the Bragg equation. However, the peak shifts to 2θ = 9.8°after adding DPDPP into the GO [Figure 3B(b)], which indicates that the interlayer spacing is slightly increased (9.1 Å).…”