Magnetic retrievable Ag/AgBr/ZnFe2O4 photocatalyst for efficient removal of organic pollutant under visible light

In the present work, a visible-light-driven Ag/AgBr/ZnFe₂O₄ photocatalyst has been successfully synthesized via a deposition–precipitation and photoreduction method. The crystal structure, chemical composition, morphology and optical properties of the as-prepared nanocomposites were characterized by X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscope, UV–vis diffuse reflectance spectroscopy and photoluminescence. The photocatalytic activities of the Ag/AgBr/ZnFe₂O₄ nanocomposites were evaluated through the photodegradation of gaseous toluene and methyl orange (MO) under visible light. The results revealed that the as-prepared Ag/AgBr/ZnFe₂O₄ nanocomposite exhibited excellent photocatalytic activity. The degrading efficiency of MO could still reach 90% after four cycles, and the Ag/AgBr/ZnFe₂O₄ nanocomposite could be recycled easily by a magnet. Additionally, the enhanced photocatalytic mechanism was discussed according to the trapping experiments, which indicated that the photo-generated holes (h⁺) and •O₂⁻ played important roles in photodegradation process. At last, a possible photocatalytic oxidation pathways of toluene was proposed based on the results of GC–MS. The Ag/AgBr/ZnFe₂O₄ composites showed potential application for efficient removal of organic pollutant.