Decolorization of RhB on three-dimensional porous CeO2/LaFeO3/SrTiO3 catalyst via photo-fenton-like catalysis.

Abstract

The catalysts with three-dimensional porous (3DP) CeO₂, LaFeO₃ and SrTiO₃ are synthesized by sol-gel method and chemical precipitation method. The resulting multi-component 3DP CeO₂/LaFeO₃/SrTiO₃ composite material featured a high specific surface area (26.08 m²/g), which can provide more surface active sites to improve adsorption capacity and catalytic performance. The photocatalytic, Fenton-like, photo-Fenton-like performance of the catalyst are studied on decolorization of RhB under UV irradiation, respectively. 3DP CeO₂/LaFeO₃/SrTiO₃ exhibits high catalytic performance. Compared with photocatalytic or Fenton-like performance, 3DP CeO₂/LaFeO₃/SrTiO₃ catalyst exhibits higher photo-Fenton-like performance, facilitating efficient decolorization of the rhodamine B. Moreover, the initial reaction rate on decolorization of RhB with 3DP CeO₂/LaFeO₃/SrTiO₃ is 10.55, 5.52, 3.67 and 1.51 times higher than that with SrTiO₃, LaFeO₃, 3DP CeO₂ and 3DP CeO₂/LaFeO₃, respectively. Meanwhile, 3DP LaFeO₃/CeO₂/SrTiO₃ has a wider pH usage range in the synergistic reaction. Finally, a catalytic mechanism for the decolorization of rhodamine B is proposed. The continuous cycling of Fe³⁺/Fe²⁺ and Ce⁴⁺/Ce³⁺ and the production of active substances are achieved under the photo-Fenton-like effect of the catalyst.