Investigation of the effect of deposition temperature of pyrolysis spray method on superhydrophobic coatings of stearic acid modified alumina nanoparticles on stainless steel

Superhydrophobicity is the tendency of the surface to repel water droplets. Due to this unique property, superhydrophobic surfaces can be used in many areas such as waterproof surfaces, anti-corrosion surfaces, antifreeze surfaces, and anti-corrosion surfaces. In the present study, the superhydrophobic surface was generated using the spray pyrolysis method. The precursor to the coating process was stearic acid-modified alumina nanoparticles dispersed in alcohol. Increasing the deposition temperature, especially after 250 oC, reduced the roughness and hydrophobicity of the samples. Examination of deposition time showed that there is an optimal time for coating. In addition to experimental studies, the electronic properties and the mechanism of stearic acid adsorption on alumina surfaces were investigated with density functional theory (DFT) and molecular dynamics (MD) simulations. The superhydrophobic surface on the stainless steel substrate was obtained using a stearic acid-modified alumina suspension in 2-propanol alcohol at a temperature of 100 oC and 90 s deposition time with a water contact angle of about 160 °.