Composite magnetic photocatalyst Bi24O31Br10/NiFe2O4: Hydrothermal preparation, characterization and photocatalytic mechanism

In this paper, composite magnetic photocatalyst Bi24O31Br10/NiFe2O4 was prepared by a simple one-step hydrothermal method. The microstructure and chemical composition of the composite were characterized by XRD, SEM, EDS, TEM, XPS, PL, EIS and ESR. The photocatalytic activity was examined by decomposing Rhodamine B (RhB) under simulated sunlight irradiation. The results showed that granular NiFe2O4 was embedded into the Bi24O31Br10 nanometer tablet, increasing the specific surface area of the composite. Moreover, the Bi24O31Br10/NiFe2O4 (10 wt%) exhibited outstanding photocatalytic activity, and the decolorization percentage of RhB can reach 99.8% after 40 min of illumination. Meantime, the composite product displayed excellent magnetic performance and photocatalytic stability, with the photocatalytic activity reaching above 90% after 5 times of recycled and reused. The improved photocatalytic performance was ascribed to the fact that a new P-P heterojunction formed between Bi24O31Br10 nanosheets and NiFe2O4 can effectively promote the separation of internal photogenerated electrons.

Automated summary

A composite magnetic photocatalyst Bi24O31Br10/NiFe2O4 was successfully prepared in this study, showing outstanding photocatalytic performance and stability in the degradation of Rhodamine B under simulated sunlight. The improved photocatalytic activity is attributed to the formation of a new P-P heterojunction between Bi24O31Br10 nanosheets and NiFe2O4, which effectively promotes the separation of internal photogenerated electrons.