Fluorine modification on titanium dioxide particles: Improving the anti-icing performance through a very hydrophobic surface

Abstract

In this study, fluorine modification was successfully conducted on titanium dioxide (TiO2) to enhance the anti-icing property through fabricating a very hydrophobic surface. TiO2 was firstly modified with 3-methacryloxypropyl-trimethoxysilane (MPS) to introduce CC bonds. Then, dodecafluoroheptyl methacrylate (DFHMA) monomers were successfully grafted on the TiO2 particles via CC bonds introduced by MPS. Herein, azobisisobutyronitrile (AIBN) was used as initiator to initiate the reaction. The chemical components of the TiO2 particles were investigated by X-ray photoelectron spectroscopy (XPS). XPS analysis of fluorine-modified TiO2 revealed that the fluorine content reached a peak value of 7.3%, while the water contact angle enhanced to a maximum value of 146°. This water contact angle value of 146° was dramatically increased by 131° in comparison with unmodified TiO2, indicating a very hydrophobic surface. The crystallization temperature of a water droplet on the corresponding fluorine-modified TiO2 decreased to −19.4 °C (10.3 °C decrease in comparison with that of a water droplet on unmodified TiO2). Also, the freezing delay time on the fluorine-modified TiO2 is more than 25 min under the testing temperature of −10 °C, exhibiting excellent anti-icing property.