Photocatalytic activity of water-based acrylic coatings containing fluorosilane treated TiO2 nanoparticles

•TiO2 nanoparticles were treated with fluorosilane in an alkaline condition.•FTIR studies confirmed fluorosilane surface treatment of TiO2 nanoparticles.•Addition of treated TiO2 to the paint provides efficient photo-catalytic property.•Durability of the coatings was studied using AFM and SEM techniques.•Uniform and superficial degradation of treated TiO2 filled coating was detected. In this study, TiO2 nanoparticles were treated with 1H,1H,2H,2H-perfluorooctyltriethoxysilane (fluorosilane) in an alkaline condition. The treated nanoparticles were added to a water-base acrylic coating to introduce photocatalytic activity. Dispersion of the nanoparticles and also Ti element wt% on the coatings’ surface were evaluated using atomic force microscopy and energy dispersive X-ray analyses, respectively. Photocatalytic activity of the coatings was investigated via study of the decomposition – under UVA irradiation – of Rhodamine B, as a pollutant model deposited on the coatings’ surface. Durability of the coatings in short-term was investigated using atomic force microscopy and scanning electron microscopy observations. Fourier transform infrared spectroscopy results confirmed the interactions between fluorosilane compound and TiO2 nanoparticles. Analyzing surface topography using atomic force microscopy analysis results showed better dispersion of the treated nanoparticles on the coatings’ surface. Energy-dispersive X-ray analysis of the coating containing fluorosilane treated TiO2 nanoparticles showed higher concentration of Ti element on the coatings’ surface. Color coordinate measurements revealed faster and more efficient decomposition of Rhodamine B dyestuff on the coatings’ surface containing FT nanoparticles under UVA irradiation. This can be related to the tendency of FT nanoparticles for migration toward the coatings’ surface, during film formation process. The durability tests results revealed a uniform degradation of the coating surface containing FT nanoparticles. Finally, TiO2 nanoparticles treated in this way may offer promising prospect for applications in self-cleaning organic coatings.