UV-Resistant and Superhydrophobic Self-Cleaning Surfaces Using Sol–Gel Processes

Abstract Inorganic superhydrophobic, low-surface energy silica coatings have been prepared using sol-gel processing with tetraethoxysilane and trifluoropropyltrimethoxysilane as precursors. When trifluoropropyltrimethoxysilane was incorporated into silica, hydrophobic trifluoropropyl groups were present on the surface, yielding hydrophobicity. When combined with the rough surfaces from a sol-gel process, superhydrophobic surfaces can be generated. The surfaces were characterized by contact angle measurements, scanning electron microscopy and atomic force microscopy. Thermogravimetric analysis was used to determine the thermal stability of the as prepared silica materials. In order to measure the surface hydrophobicity retention of the silica surfaces under UV irradiation, UV accelerated aging tests were conducted according to ASTM D 4329.