Photoactivity of Fe and Zn-doped TiO2 in phenol degradation under visible light

Abstract

This study developed bandgap energy of TiO2 into the visible region for the photo-activation. The photocatalytic performance of TiO2 was improved when Fe-doping at 2% and 4% by weight, Zn-doping at 2% and 4% by weight, and doping Fe/Zn 1+1% and 2+2% by weight using flame spray pyrolysis as a synthesis method. Brunauer-Emmett-Teller (BET), ultraviolet-visible spectroscopy (UV-Vis), and x-ray diffraction (XRD) were used to characterize the properties of synthesized and all doped TiO2 photocatalysts. To prove the effectiveness, all the modified TiO2 were also compared with the pure synthesized TiO2 by performing photodegradation of phenol under 1hr visible light. The remaining phenol concentration was estimated using gas chromatography-flame ionization detector (GC-FID). Doped TiO2 enhances smaller grain size, larger specific surface area and narrower the bandgap energy after comparing with the pure synthesized TiO2. Zn-doped leads to large surface area that improved the photocatalytic activity of catalyst. However, there was no significant synergistic effect between Fe and Zn doping. The optimum condition for phenol photodegradation was at about 4%Fe doped TiO2.