Synergistic effect of TiO2 and iron oxide supported on fluorocarbon films. Part 1: Effect of preparation parameters on photocatalytic degradation of organic pollutant at neutral pH

Iron oxide and TiO2 were immobilized on modified polyvinyl fluoride films in a sequential process. Synergic effects of iron oxide and TiO2 on the polymer film were observed during the heterogeneous degradation of hydroquinone (HQ) in the presence of H2O2 at pH close to neutrality and under simulated solar irradiation. Within the degradation period, little iron leaching (<0.5 mg/L) was observed.The surface of commercial polyvinyl fluoride (PVF) film was modified by TiO2 under light inducing oxygen group (C–OH, CO, COOH) formation on the film surface. During this treatment, TiO2 nanoparticles simultaneously bind to the film, leading to PVFf–TiO2. The possible mechanistic pathway for the TiO2 deposition and the nature of the polymer–TiO2 interaction are discussed. Furthermore PVF and PVFf–TiO2 were immersed in an aqueous solution for the deposition of iron oxide layer by hydrolysis of FeCl3, leading to PVF–Fe oxide and to PVFf–TiO2–Fe oxide respectively.HQ degradation and mineralization mediated by PVFf–TiO2, PVF–Fe oxide and PVFf–TiO2–Fe oxide were investigated under different conditions. Remarkable synergistic effects were observed for PVFf–TiO2–Fe oxide possibly due to Fe(II) regeneration, accelerated by electron transfer from TiO2 to the iron oxide under light.