Fabrication of Superhydrophobic Self-Cleaning Coatings by Facile Method: Stable after Exposure to Low Temperatures and UV Light

Abstract

Self-cleaning hydrophobic surfaces attracted public attention last few decades after discovering of lotus ef-fect. Ability of lotus leaves to keep cleanness in relatively dirty places and to clean up itself during rains di-rected to the development of novel materials and surface structure modification. The surface with such smart properties may have potential in cost-effectiveness in case of application it in skyscrapers, high buildings, etc. Two main criteria for the surface to express hydrophobic behavior are roughness and low surface energy of the coating material. In this study, superhydrophobic self-cleaning coatings were prepared by simple, facile and cheap method using easily available materials such as polydimethylsiloxane (PDMS) and TiO2 nanopar-ticles and fully characterized for direct usage. PDMS is a bonding layer and TiO2 nanoparticles are a rein-forced composite to form roughness, which shows superhydrophobicity. Characterizations showed that the as prepared superhydrophobic coating has a water contact angle up to 165.5°, with sliding angle of less than 5º. Also self-cleaning and surface microfluidic properties have been studied. The superhydrophobic properties of these coatings do not change even after exposure its surface to low temperatures and UV light. SEM images confirm rough structure of obtained surface on glass and sand grains