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

Abstract

In the present work, a visible‐light‐driven Ag/AgBr/ZnFe 2 O 4 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/ZnFe 2 O 4 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/ZnFe 2 O 4 nanocomposite exhibited excellent photocatalytic activity. The degrading efficiency of MO could still reach 90% after four cycles, and the Ag/AgBr/ZnFe 2 O 4 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 •O 2 − 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/ZnFe 2 O 4 composites showed potential application for efficient removal of organic pollutant.