Preparation of superhydrophobic and oleophobic antireflective coating with high transmittance

Abstract

The multifunctional coatings with hydrophobicity, oleophobicity, and antireflection have great practical application value. In this work, the mixed sol of alumina sol and silica sol prepared by the sol-gel method was deposited on both sides of glass substrates by dip-coating method. After the calcined coating was treated with hot water at 90 °C, the coating changed from smooth to grass-like hierarchical nanoflakelets, and the uneven distribution of silica nanospheres on grass further increased the porosity of the coating and formed a more complex double nano-scale structure. Finally, the coating was modified with PFDTES by the chemical vapor deposition method (CVD). The results showed that the highest transmittance of the coating reached 99.59% in the visible wavelength range of 400–800 nm, the contact angles of water, glycerin, ethylene glycol, and soybean oil were 175°, 150°, 140°, 120°, respectively, and the rolling angle of water is less than 3°. The coating has multiple functions of high transmittance, superhydrophobicity, and oleophobicity. In addition, the coating has significant resistance to chemical erosion, mechanical stress, and ultraviolet radiation, showing great potential for practical application.