Comparative evaluation of polymer surface functionalization techniques before iron oxide deposition. Activity of the iron oxide-coated polymer films in the photo-assisted degradation of organic pollutants and inactivation of bacteria

The preparation of iron oxide-coated polymer films and their photocatalytic activity in organic pollutants degradation and bacterial inactivation is described. Polyvinyl fluoride (PVF), polyethylene (PE) and polyethylene terephtalate (PET) films were used as catalyst supports. Polymer surfaces were functionalized by vacuum-UV radiation (V-UV) and radio-frequency plasma (RF-P); and also by photo-Fenton oxidation (P-FO) and TiO2 photocatalysis (Ti-PC) in solution. These pre-treatments were performed to improve iron oxide adhesion on the commercial polymer surface. The functionalized polymers films (Pf) were afterward immersed in an aqueous solution for the deposition of iron oxide layer by hydrolysis of FeCl3. The photocatalytic activities of iron oxide-coated functionalized polymers films (Pf-Fe oxide) prepared by different methods were compared during hydroquinone degradation in presence of H2O2. RF-P and Ti-PC pre-treated polymers showed significantly higher photocatalytic activity and long-term stability during processes leading to pollutant abatement, if compared with not treated ones (NT), although similar leaching of iron was observed for all the materials. PET bottles (PETb) were used as reactor and catalyst supports. The produced PETbf-Fe oxide surfaces were efficient in photo-assisted bacterial inactivation in the presence of H2O2, and no dissolved iron species were detected in solution.