Abstract:Alumina gel film was prepared by the sol-gel and dip-coating method using Al(O-sec-Bu)3 as a precursor. Then an alumina film with both superhydrophobicity and high adhesive force was fabricated by treatment procedures as heat, boiling water, and surface modification with PEI and STA. The chemical composition, morphology, structure, and wettability of the superhydrophobic surface were investigated by techniques as FTIR, FE-SEM, XRD, and contact angle measurement. Results show that the alumina surface is made up of the porous flowerlike structure coated with a layer of long hydrophobic alkyl chains. Water is expected to enter into the large scale grooves of the rough alumina surface, but it can not enter into the small scale ones. Consequently, the alumina surface shows both high contact angle and strong adhesion.
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