Novel nanoparticle-assembled tetrakaidekahedron Bi25FeO40 as efficient photo-Fenton catalysts for Rhodamine B degradation

In this study, nanoparticle-assembled Bi25FeO40 materials were synthesized by a novel and simple process, and their microstructure was regulated by different methods of adding Bi3+ and Fe3+. The novel nanoparticle-assembled tetrakaidekahedron Bi25FeO40 materials exhibited more oxygen vacancy and larger specific surface area than irregular or cubic-like Bi25FeO40 microcrystals and revealed better photo-Fenton catalytic oxidation activity toward degrading Rhodamine B (RhB) pollutants. These novel materials activated H2O2 in visible light to produce non-free radicals 1O2 and hole (h+) active oxidative species that dominated the catalytic degradation of RhB. Complete degradation of RhB was achieved after 1 h. The possible reaction mechanisms of the photo-Fenton catalytic system are discussed in detail by radical scavenging tests, X-ray phosphorescence analysis, and electron paramagnetic resonance spectroscopy. The results provided a way to rationally explore and construct photo-Fenton catalysts for wastewater treatment. [Display omitted] •A novel Bi25FeO40 tetrakaidekahedron material was initially synthesized.•Oxygen vacancy could be regulated by controlling the morphology of Bi25FeO40.•The tetrakaidekahedron Bi25FeO40 exhibited highest photo-Fenton activity.•Oxygen vacancy and surface area played a synergistic role in catalysis.•The photo-Fenton mechanism was systematically investigated and proposed.