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/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.

Magnetic Metal Oxide-Based Photocatalysts with Integrated Silver for Water Treatment

“…The photocatalytic enhancement observed in a Ag/ZnFe 2 O 4 nanocomposite can be attributed to electron storage in the Fermi energy of the Ag nanoparticles, as shown in Figure 8a [70]. However, in the case of Ag/AgBr/ZnFe 2 O 4 (Figure 8b) [155], photoexcited electrons from the ferrite as well as plasmon-excited electrons from the Ag nanoparticles are transferred to the CB of AgBr, resulting in efficient generation of photocatalytic active species. As for the magnetic properties of magnetic silver-integrated composites specifically, the ease of separation and recovery of the composite photocatalyst from the treated solution is often reported [20,63,153,160].…”

Study on Adsorption and Photocatalytic Properties of Zinc Ferrite

“…It was found that co-doped zinc ferrite (Zn 0.50 Cu 0.50 Fe 1.90 Bi 0.10 O 4 and Zn 0.50 Cu 0.50 Fe 1.95 Ce 0.05 O 4 ) nanoparticles exhibited a higher bisphenol A removal efficiency than the doped and un-doped zinc ferrite nanoparticles. Li et al [18] successfully synthesized a visible-light-driven Ag/AgBr/ZnFe 2 O 4 photocatalyst via a deposition-precipitation and photoreduction method. The prepared Ag/AgBr/ZnFe 2 O 4 nanocomposites exhibited high photocatalytic activities for the degradation of gaseous toluene and MO.…”