A Study on Impact of Hydrophobic Effect on Al2O3 Coated Glass by Sol–Gel Dip Coating Method for Automobile Windshield Application

This work aimed to achieve hydrophobic effect on aluminum based on nano/micro hierarchical surface structure through sol–gel coating technique. A hydrophobic coating for glass substrates was developed using Tetraethyl orthosilicate Si(OC2H5)4 synthesized with Al2O3 nanoparticles. The sol was prepared by adding the Al2O3 nanoparticles to sol just before the coating process and dispersing. The coating process was conducted using a sol–gel dip coating deposition method. The effect of functionalization of Al2O3 nanoparticles to prepare the highly dispersed nanoparticles has been investigated in detail. The surface morphology was characterized by field emission scanning electron microscopy (FESEM), and surface roughness were measured. The effect of Al2O3 on the hydrophobicity of the coating was evaluated using contact angle measurements. The results reveal that water contact angles improved with the addition of Al2O3 nanoparticle wt% 0.5, 1, and 1.5 g. The glass coated with higher wt% of Al2O3 nanoparticle exhibits a water contact angle of 113° with an effect to lower surface roughness value of 0.011 μm. A water repelling coating on the glass is developed with the incorporation of Al2O3 nanofiller via sol–gel synthesis method.