Harnessing LDHs@GO hierarchical nanocomposites for robust and efficient corrosion protection in sustainable marine concrete infrastructure

Marine environments exacerbate the deterioration of reinforced concrete structures, primarily through chloride ion-induced corrosion of the reinforcement. Here, inspired by coral, we constructed layered double hydroxides-graphene oxide (LDHs@GO) nanocomposite by in-situ growing LDHs on the surface of GO, designed to develop ultrahigh corrosion-resistant marine concrete. This LDHs@GO nanocomposite features a highly open architecture with a significantly increased specific surface area (92.65 m²/g) and pore volume (0.15 cm3/g). Experimental results and density-functional theory (DFT) calculations reveal the LDHs@GO nanocomposite’s superior performance in both simulated concrete pore solutions and real seawater environments. With 3 wt% LDHs@GO, chloride adsorption capacities of cementitious composites increase by 67.3% (endogenous ions) and 67.6% (exogenous ions), while the corrosion current density and corrosion inhibition efficiency is 0.0064 µA/cm2 and 80.9%, and 0.0373 µA/cm2 and 70.7% for seawater-mixed and NaCl-immersed reinforced cementitious composites after 620 days, respectively. Such remarkable anticorrosion performance primarily arises from the potent physical barrier effect against free chloride migration, the superior chloride adsorption capacity of LDHs@GO with abundant interlayer adsorption sites, and refined pore structures. This work highlights the practical potential of rationally designed LDHs@GO for sustainable marine infrastructure development, offering long-term, efficient corrosion protection.