A simple way to fabricate an aluminum sheet with superhydrophobic and self-cleaning properties

Abstract

A superhydrophobic aluminum sheet is fabricated via a hot water immersing process and subsequently surface modification with heptadecafluorodecyltrimethoxy-silane (HTMS). As revealed by the scan electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectrophotometer (FTIR) results, a rough pseudoboehmite film is formed on the aluminum sheet, and HTMS molecules are grafted on the film surface successfully. These two factors make the treated aluminum sheet present superhydrophobicity with a water contact angle larger than 160° and sliding angle less than 5°, and possess a self-cleaning property. Furthermore, the flexible superhydrophobic aluminum sheet could be pasted to a cylinder surface without destroying its superhydrophobicity. At the end, the effect of hot water treatment time on superhydrophobicity is investigated.