We present a facile method for fabrication of Titania (TiO2) based superhydrophobic surfaces by silanization with wettability switching from superhydrophobic to superhydrophilic under ultraviolet (UV) light irradiation. The dynamic of surface wettability under UV irradiation was tested under ambient environment as well as in oily environment. We synthesized TiO2 based superhydrophobic surface with contact angle as high as 154º for advancing angle and 152ºfor receding angle in air. A dramatic decrease of the contact angle to 0º was observed when the TiO2 sample was irradiated with UV light. No appreciable change in contact angle was observed when sample was tested under oily medium. However, a switching from Cassie state to Wenzel state was occurred, resulting in a sticky superhydrophobic surface. Photocatalyic activity induced in organic degradation was probably the major cause of the wettability switching.
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