Synthesis and characterization of superhydrophobic alumina-silane sol-gel coating / Ahmad Lutfi Anis, Mahesh Kumar Talari and Widyani Darham

Superhydrophobic surfaces have attracted significant research interest because of their use for design of water-repellent and self-cleaning coatings. A superhydrophobic surface can be created by modifying a rough surface with a material of low surface energy through a sol-gel coating technique. Adjusting the amount of precursor and the low surface energy material can optimize the hydrophobicity of the coating. In this work, different ratios (4:1, 3:2, 1:1 and 2:3) of silane: alumina coatings were synthesized and applied on glass substrates through sol-gel method. Characterization of the coated samples showed that volume ratios of silane sol and alumina sol in sol-gel coating affected the superhydrophobicity of the coated glass substrate. The solution of alumina sol and silane sol with ratio 4:1 produced superhydrophobic films with contact angle for water larger than 150 and FESEM images showed very intense roughness compared to the other ratios.