Superoleophobicity of a Material Made from Fluorinated Titania Nanoparticles

Superoleophobic surface prepared by using perfluorooctanoic acid modified titania (TiO2) nanoparticles is described. A variety of liquids, ranging from water to organic liquids, even the volatile liquids, such as toluene, chloroform and tetrachloromethane, exhibit typical spherical shapes on the fluorinated TiO2 surface with the contact angles of over 150 degrees and easily roll off at a small tilt angle. The reasons of the superoleophobicity of the fluorinated TiO2 nanoparticles are particularly discussed in detail. Besides the low surface energy and rough structure, the adhesion of TiO2 particles at the bottom of liquid droplets is considered as a crucial factor to obtain the superoleophobicity.