Facile fabrication of novel superhydrophobic Al2O3/polysiloxane hybrids coatings for aluminum alloy corrosion protection

AA2024 aluminum alloy is a kind of wildly used metal material for its excellent mechanical performance, but the inevitable corrosion reaction will seriously decrease its strength and service life. How to delay the corrosion damage of AA2024 aluminum alloy is a challenging task. Herein, a kind of novel superhydrophobic coatings constructed by Al 2 O 3 /siloxane hybrids were in-situ grown on aluminum alloy surface through a simple, environmentally friendly and efficient method. Firstly, rough Al 2 O 3 micro-nano layers were easily prepared on the surface of aluminum alloy by simple anode oxidation treatment in a mild condition. At the meanwhile, polyoctyltriethoxysilane was chemically deposited on the surface of Al 2 O 3 micro-nano layers, leading to the formation of Al 2 O 3 /polysiloxane hybrids. Benefiting from the pristine hydrophobic effect of polyoctyltriethoxysilane and the rough hierarchical micro/nano-structure of the electro-assisted synthesis of aluminum oxide, the as-synthesized Al 2 O 3 /polysiloxane hybrids exhibited excellent superhydrophobic property with ultra-high contact angle (above 170°) and ultra-low sliding angle (close to 0°). Basing on this, excellent corrosion resistance efficiency was achieved in NaCl solution, acidic and alkaline environment for the AA2024 aluminum alloy. Besides, the Al 2 O 3 /polysiloxane hybrids coated aluminum alloy displayed satisfied chemical and storage stability. Considering the strategy proposed in this work owns the advantages of simplicity, convenience and environmental protection, this work may provide effective guidance for constructing effective superhydrophobic coatings on other metal materials. • Eco-friendly method for the preparation of superhydrophobic coatings. • Ultrahigh water contact angle and ultralow sliding angle was achieved. • The prepared coatings displayed excellent corrosion resistance. • Potential guidance for synthesizing other superhydrophobic coatings.