Photocatalytic, superhydrophilic, self-cleaning TiO2 coating on cheap, light-weight, flexible polycarbonate substrates

Abstract

Photocatalytic TiO2/SiO2 coatings with excellent superhydrophilic wettability were prepared on light-weight polycarbonate substrates for self-cleaning applications. The effect of distinct SiO2 concentrations (0–40%) in TiO2 on the morphology, wettability, UV–Vis transmittance, haze, and durability of the coatings was studied in detail. TiO2/SiO2 coatings prepared with 20% silica in TiO2 showed superhydrophilic wetting properties with a smooth and uniform morphology with more than 85% transmittance. The lower haze value of TiO2/SiO2 coatings confirms their clear optical appearance. A low-friction layer of fluoroalkylsilane was applied to the coatings to improve their mechanical durability. In addition, the hydrophobic-hydrophilic patterns of different areas were prepared to check their effect on the haze and wetting properties.