Built-in electric field enhanced BiFeO3 photo-Fenton degradation Rhodamine B solution

BiFeO3 nanoflakes (BFO NFs) were synthesized via a facile hydrothermal route. The crystal structure, morphology, specific surface area and optical properties of the flakes were characterized by X-Ray Diffraction (XRD), Brunner–Emmet–Teller measurements (BET) and UV–vis Diffuse Reflectance Spectrum (UV–vis DRS). The results showed that the thickness and diameter of BFO NFs are 100–150 nm and 1.0–1.2 μm, respectively. Moreover, the results of UV–vis DRS indicated that BFO NFs exhibits good response to the visible light and the bandgap was calculated to be 2.2 eV according to the Kubelka–Munk theory. The photo-Fenton performance of BFO NFs was obviously enhanced due to the piezoelectric effect for the degradation efficiency of Rhodamine B (Rh B) (10 mg L−1) within 60 min and greatly elevated from 72 to 97%. The intermediate active species of ·O2− and ·OH were detected by radical capture experiments and Electron Spin Resonance (ESR). The possible catalytic mechanism was proposed based on the above experiments results. In previous researches about photo-Fenton reaction, the piezoelectric properties of BFO NFs were rarely mentioned. This study represents a potential approach toward waste water treatment.