Superamphiphobic organosilane-grafted attapulgite as an effective corrosion-resistant and anti-icing coating for aluminum alloy

The corrosion protection and ice-over delay of aluminum alloys have always been pressing issues. Lotus-inspired superhydrophobic materials show great potential in the field of corrosion prevention and delayed icing, but they are currently prone to failure due to wetting and adhesion by low surface tension liquids. In this paper, we constructed a superamphiphobic (superhydrophobic and superoleophobic) organosilane-grafted attapulgite (OG-ATP) coating on 5083 aluminum alloy substrates using ATP, tetraethyl orthosilicate (TEOS), and 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFAS) through hydrolysis-condensation reaction and spray-coating technique. The coating exhibits contact angles greater than 150º and sliding angles less than 10º for water, glycerol, ethylene glycol, peanut oil, and even n-hexadecane with surface tension@20ºC of 27.5 mN/m. Through studying surface morphologies, chemical compositions, electrochemical behaviors, self-cleaning, and anti-icing performance, it was found that the Rct and |Z|0.01Hz of the protected aluminum alloy increased by four orders of magnitude with a corrosion inhibition efficiency of 99.99%, demonstrating excellent anti-corrosion functionality. Additionally, icing test results at -5°C, -10°C, and -15°C show that the prepared coating exhibits significant delayed icing performance. We believe that the integration of properties such as water-oil repellency, self-cleaning, anti-corrosion, and anti-icing will enable superamphiphobic materials to demonstrate enormous application prospects in various fields.