A one step self-cleaning surface with robust superhydrophobic and photocatalytic properties: Electrostatic sprayed fluorinated ethylene propylene mixed with nano TiO2–SiO2 particles

In this research, a one-step and environmentally friendly method, free from the complexity of chemical techniques, was utilized to prepare a superhydrophobic surface that can be implemented on large scale. To this end, at first, silica nanoparticles were made hydrophobic through the silanization method, then got mixed with titanium dioxide nanoparticles and fluorinated ethylene propylene (FEP). Afterward, the combined materials were deposited on aluminum substrate using an electrostatic spraying method. In order to assess the fabricated surface, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and contact angle measurement are accomplished. In addition, the photocatalytic activity by the degradation of oleic acid and methylene blue (MB) upon UV exposure was studied. Results indicated formation of a superhydrophobic photocatalyst with contact angle over 150°. This superhydrophobic surface containing nano silica content 12 wt% and TiO2 20 wt% exhibited excellent photocatalytic activities in the organic materials degradation. The obtained photocatalyst surfaces also revealed proper stability in acidic (pH = 5) and alkaline (pH = 11) media. Moreover, a suitable stability was observed in the fouling medium with duration 10 h while no change in the static contact angle occurred.