Superhydrophobic NiAl-LDHs Composite Coating for Long-Term Corrosion Resistance of Al Substrates

Superhydrophobic surfaces exhibit tremendous potential in corrosion-resistant applications due to their unique surface structures and properties. Herein, a NiAl-LDHs composite coating was first produced on an Al substrate surface by VO₄^3- anion intercalation and modified with stearic acid (SA). The final as-prepared SA-LDHs-VO₄^3- coating exhibited excellent hydrophobicity and self-cleaning abilities, with a water contact angle of about 155.7 ± 1.5°. Furthermore, the corrosion current density of SA-LDHs-VO₄^3--covered Al material was reduced by approximately 4 orders of magnitude compared to the untreated Al substrate. According to the test, the corrosion resistance efficiency of SA-LDHs-VO₄^3--covered Al material reached as high as 99.95%, which indicated the significant ability of the coating to strengthen the corrosion resistance of the Al substrate. After 28 days of immersion, the SA-LDHs-VO₄^3- coating maintained over 90% corrosion resistance efficiency and with a water contact angle above 120°. These results demonstrated the bright prospect of the as-prepared SA-LDHs-VO₄^3- coating for a wide range of applications in corrosion resistance.