Chemistry of the Fe₂O₃/BiFeO₃ Interface in BiFeO₃ Thin Film Heterostructures

Single-phase BiFeO3 and BiFeO3-Fe2O3 nanocomposite photocatalysts for photodegradation of organic dye pollutants

The application of a novel BiFeO₃ (BFO)-Fe₂O₃ composite (called BFOF) as a photocatalyst for the degradation of methylene blue is reported. To improve the photocatalytic effectiveness of BiFeO₃, we synthesized the first BFOF photocatalyst by adjusting the molar ratio of Fe₂O₃ in BiFeO₃ using microwave-assisted co-precipitation. The UV-visible properties of the nanocomposites showed excellent absorption of visible light and reduced electron-hole recombination properties compared to the pure phase BFO. Photocatalytic studies on BFOF10 (90% BFO, 10% Fe₂O₃), BFOF20 (80% BFO, 20% Fe₂O₃), and BFOF30 (70% BFO, 30% Fe₂O₃) have shown that they decompose Methylene Blue (MB) in sunlight better than the pure BFO phase in 70 minutes. The BFOF30 photocatalyst was the most effective at reducing MB when exposed to visible light (94%). Magnetic studies confirm that the most effective catalyst BFOF30 has excellent stability and magnetic recovery properties due to the presence of magnetic phase Fe₂O₃ in the BFO.