Due to its special two-dimensional lamellar structure, graphene possesses an excellent shielding effect, hydrophobic characteristics and large specific surface area, which can effectively isolate the internal structure from the external corrosive media. However, lamellar graphene is easy to stack and agglomerate, which limits its anti-corrosion performance. In this paper, cerium oxide-graphene oxide (CeO2-GO) nanocomposites were prepared by a hydrothermal synthesis method. Field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) were applied for microstructure examination, showing that a large number of nanoscale granular cerium oxide grew on the lamellar graphene oxide surface, which improved the dispersion performance of graphene inside the matrix. The anti-corrosion properties of the coating were analyzed and illustrated by open circuit potential (OCP), frequency response analysis, Tafel curve and Mott–Schottky curve. The results indicated that the CeO2-GO (4:1) nanocomposite not only eliminated the agglomeration of graphene to some extent, but also prepared the graphene epoxy coating with good dispersion, which further promoted its anti-corrosion performance. The paper proposed a feasible solution for GO dispersion in cement-based materials and lays a solid theoretical foundation for the engineering application of cerium oxide-graphene oxide modified anticorrosive coating.

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Graphene is a two-dimensional sheet of regular hexagonal honeycomb lattice formed by sp2 hybrid orbital bonding, with only one layer thickness of a single atom, which is known as the “super king” of the 21st century. Previous studies have shown that cerium oxide-graphene oxide (CeO2-GO(4:1)) nanocomposites eliminated the agglomeration of graphene to some extent and the CeO2-GO(4:1) epoxy coating could be prepared with good anti-corrosion performance. In this paper, CeO2-GO(4:1) nanocomposites were prepared by the hydrothermal synthesis method, and the three-electrode method was used for electrochemical tests. The state evolution of CeO2-GO(4:1)/EP coating and the synergy between CeO2-GO(4:1)/EP and corrosion inhibitor in simulated seawater solution with different concentrations (20%, 40%, 60%) were analyzed and illustrated by Optical Microscope (OM) characterization, Open Circuit Potential (OCP), Electrochemical alternating current Impedance Spectroscopy (EIS), Mott–Schottky curve and Tafel curve. The results indicated that CeO2-GO(4:1) nanocomposites showed good corrosion resistance in a marine environment. This research lays a solid theoretical foundation for the application of cerium oxide-modified graphene oxide anticorrosive coating in marine engineering.

Concrete is a multi-phase, porous system. The pore structure has an important influence on the properties of the concrete. In this paper, a kind of fiber reinforced mortar was prepared with desert sand and its pore structure was studied. The MIP technique was used to investigate the pore structure characteristics between 1 nm and 500 μm (in diameter). Meanwhile, the μX-CT technique was used to study the pore structure characteristics above 200 μm. It was found that the total porosity tends to decrease first and then increase as the dosage of desert sand increased. The porosity decreased gradually from the upper to bottom area inside the sample, and the diameter of the air voids near the upper area became larger. After curing for 28 days, the compressive strength of fiber reinforced mortar reached the maximum when the content of desert sand was 50%. In conclusion, the appropriate amount of desert sand can reduce the porosity of the fiber reinforced mortar to some extent and the number of large size air voids can be significantly reduced, which improves the pore structure and the mechanical properties of the fiber reinforced mortar.