Preparation of an antibacterial, hydrophilic and photocatalytically active polyacrylic coating using TiO₂ nanoparticles sensitized by graphene oxide

In recent years more attentions have been paid for preparation of coatings with self-cleaning and antibacterial properties. These properties allow the surface to maintain clean and health over long times without any need to cleaning or disinfection. Acrylic coatings are widely used on various surfaces such as automotive, structural and furniture which their self-cleaning and antibacterial ability is very important. The aim of this work is the preparation of a polyacrylic based self-cleaning and antibacterial coating by the modification of TiO₂ as a coating additive. TiO₂ nanoparticles were sensitized to the visible light irradiation using graphene oxide through the preparation of TiO₂/graphene oxide nanocomposite. Graphene oxide was prepared via a modified Hummers method. TiO₂/graphene oxide nanocomposite was used as additive in a polyacrylic coating formulation. Hydrophilicity, photocatalytic and antibacterial activities as well as coating stability were evaluated for TiO₂/graphene oxide modified polyacrylic coating and compared with that of pristine TiO₂ modified and unmodified polyacrylic coatings. TiO₂/graphene oxide nanocomposite and polyacrylic coating modified by TiO₂/graphene oxide additive were characterized using FT-IR, UV-Vis, XRD, and FESEM techniques. The effect of TiO₂/graphene oxide composition and its percent in the coating formulation was evaluated on the polyacrylic coating properties. Results showed that polyacrylic coating having 3% W TiO₂/graphene oxide nanocomposite additive with TiO₂ to graphene oxide ratio of 100:20 is the best coating considering most of beneficial features such as high photodecolorization efficiency of organic dye contaminants, high hydrophilicity, and stability in water. According to the results, TiO₂ is effectively sensitized by graphene oxide and the polyacrylic coating modified by TiO₂/graphene oxide nanocomposite shows good photocatalytic activity under visible light irradiation.