Facile synthesis of transparent superhydrophobic titania coating by using soot as a nanoimprint template

Abstract

This paper develops a robust method for the facile synthesis of transparent superhydrophobic TiO₂ film by using the flame soot layer as a nanoimprint template. After the nanoimprint and calcination process, the TiO₂ coating exhibited the inverse roughness structure of the soot layer with high transparent properties. And subsequent hydrophobic modification with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS) rendered the transparent surfaces superhydrophobic (168 ± 4° for water). The transparency and superhydrophobicity of the TiO₂ coating could be controlled by adjusting the initial concentration of the TiO₂ suspension. The coating possesses excellent chemical stabilities and good mechanical resistance. Moreover, a superhydrophobic–superhydrophilic micropattern was further fabricated by illumination with ultraviolet light through a photomask. This fabrication process is expected to be extended to other transparent superhydrophobic coatings and to be used in many research fields.