Spray-Deposition of an Organic/Inorganic Blend for Fabrication of a Superhydrophobic Surface: Effect of Admixing with Silica Aerogel and Modified Silica Nanoparticles

Abstract

Superhydrophobic and self-cleaning glass slides were fabricated using a facile and low-cost method through spray-coating of four types of blends consisting of stearic acid, the mixture of stearic acid and SiO₂ nanoparticles, the mixture of stearic acid and SiO₂ nanoparticles modified with oleic acid, and the mixture of stearic acid and SiO₂ aerogel onto the surface. The nanocoated surfaces were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and water contact angle (WCA) measurements. The results have shown that the mixture of stearic acid and SiO₂ nanoparticles modified with oleic acid coating possessed the highest contact angle of about 158.6° and a low sliding angle while the mixture of stearic acid and SiO₂ aerogel had an almost similar WCA but with a more satisfactory durability. In contrast, the stearic acid coating alone had a hydrophobic property and the mixture of stearic acid and unmodified SiO₂ nanoparticles showed superhydrophobic properties without any self-cleaning and durability features.