Fabrication of Cu2O/Bi25FeO40 nanocomposite and its enhanced photocatalytic mechanism and degradation pathways of sulfamethoxazole

Abstract In the study, cuprous oxide (Cu2O) combined with sillenite bismuth ferrite (Bi25FeO40) was successfully fabricated through hydrothermal strategy. Subsequently, physicochemical properties of Cu2O/Bi25FeO40 were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption/desorption, X-ray photoelectron spectroscopy measurements (XPS), UV visible diffuse reflectance spectroscopy (DRS). The experimental results indicated that Cu2O/Bi25FeO40 exhibited a significantly enhanced photocatalytic activity, which 85.0% of sulfamethoxazole was decomposed in 120 min under irradiation. Afterwards, scavenger experiments have been carried out to determine the contributions of different species and h+ and H2O2 were manifested to be staple reactive species during the process of sulfamethoxazole (SMX) degradation. In addition, Cu2O/Bi25FeO40 nanocomposite showed good stabilities. And the degradation efficiency of SMX still reached 84.9% after five recycle experiments. Furthermore, some plausible degradation pathways of sulfamethoxazole were detected by a high-performance liquid chromatography-tandem mass spectrometry. Finally, the enhanced visible light photocatalytic mechanism was proposed reasonably. Eventually, this study provides a novel strategy to prepare catalyst which could be potentially applied in emerging pollutants elimination.