Synergistic control of wetting resistance and corrosion inhibition by cerium to enhance corrosion resistance of superhydrophobic coating

Superhydrophobic coatings have attracted significant attention in the anti-corrosion protection. However, their long-term corrosion resistance is still challenging under the penetration of corrosive media. In this work, we report an one-step electrodeposition method to fabricate a cerium-based superhydrophobic (CS) coating on the surface of Al alloy. The effects of cerium ions on the morphology, roughness, anti-wettability and anti-corrosion property of the coatings were investigated in detail. The results indicated that cerium ions can effectively control the anti-wetting properties of the coating surface by regulating surface micro/nanostructure during electrodeposition process. The obtained CS coating has the best corrosion protection when the cerium ion concentration is 0.0125 mol/L, and its impedance modulus changes slightly, reaching 3.16 × 10 6 Ω cm 2 after immersing in 3.5 wt% NaCl solution for 192 h. Notably, the CS coating could form a Ce-rich passive layer during the immersion to prevent further corrosion, exhibiting excellent long-term corrosion resistance. Consequently, cerium ions can enhance the corrosion inhibition behavior of such coating through the synergistic effect of regulating the surface micro/nanostructure and the active inhibition of cerium.