Synthesis of a WO3 photocatalyst with high photocatalytic activity and stability using synergetic internal Fe3+ doping and superficial Pt loading for ethylene degradation under visible-light irradiation

Abstract

Ethylene (C₂H₄) is harmful for storage and fresh-keeping of fruits and vegetables. Photocatalytic technology is an effective and environmentally friendly approach for degrading ethylene. Herein, we first report the synthesis of a WO₃ photocatalyst with high photocatalytic activity and stability using synergetic internal Fe³⁺ doping and superficial Pt loading for ethylene degradation under visible-light irradiation. Internal Fe³⁺ doping not only enhances the visible-light absorption but also improves the stability to some degree due to more positive reduction potential of Fe³⁺/Fe²⁺ than that of W⁶⁺/W⁵⁺ and separation efficiency of the photo-generated carriers. Furthermore, the loading of Pt as a co-catalyst through the photo-reduction of H₂PtCl₆ on the surface of Fe-doped WO₃ promotes the effective transfer of photo-generated electrons and reduces the photo-corrosion of WO₃. Due to the synergistic effect, extremely high degradation speed can be achieved by doping 0.25 mol% Fe and loading 0.75 wt% Pt for WO₃, which exceeds that of pristine WO₃ by about 3.3 times under visible-light irradiation. In addition, due to the excellent stability of Pt@Fe-doped WO₃, it has good industrial application prospects in the field of photocatalysis.