A simple and effective synthesis of magnetic γ-Fe2O3@SiO2@TiO2-Ag microspheres as a recyclable photocatalyst: dye degradation and antibacterial potential

Bahareh Dabirvaziri; Mohammad Hadi Givianrad; Iman Sourinejad; Ali Mashinchian Moradi; Pargol Ghavam Mostafavi

doi:10.1007/s40201-019-00410-w

A simple and effective synthesis of magnetic γ-Fe₂O₃@SiO₂@TiO₂-Ag microspheres as a recyclable photocatalyst: dye degradation and antibacterial potential

J Environ Health Sci Eng. 2019 Nov 14;17(2):949-960. doi: 10.1007/s40201-019-00410-w. eCollection 2019 Dec.

Authors

Bahareh Dabirvaziri¹, Mohammad Hadi Givianrad², Iman Sourinejad³, Ali Mashinchian Moradi⁴, Pargol Ghavam Mostafavi¹

Affiliations

¹ 1Department of Marine Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
² 2Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.
³ 3Department of Fisheries, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran.
⁴ 4Department of Marine Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

Abstract

Purpose and methods: In this study, an effective technique for synthesizing γ-Fe₂O₃@SiO₂@TiO₂-Ag magnetically separable photocatalyst was introduced by combining co-precipitation, sol-gel, and photo-deposition methods. A series of analyses including FTIR, SEM, EDS, XRD, and VSM were applied to characterize the prepared materials and the investigations on photocatalytic activity of the prepared composites were accomplished.

Results: Compared to bare γ-Fe₂O₃@SiO₂@TiO₂, the Ag-doped composite was more active in terms of photocatalytic characteristics. By applying γ-Fe₂O₃@SiO₂@TiO₂-Ag, the decomposition rate of the Basic blue 41 reached to about 94% after 3 h of UV irradiation; this rate was 63% for pure γ-Fe₂O₃@SiO₂@TiO₂. The results indicated that the dye degradation kinetics followed first-order kinetic model. During the five cycles of separation, it was observed that the Ag-doped composite was greatly effective and stable in terms of recycling. Moreover, the results indicated that antibacterial activity of γ-Fe₂O₃@SiO₂@TiO₂-Ag was remarkably stronger than that of pure Fe₂O₃@SiO₂@TiO₂ particles.

Conclusion: It was concluded that by modifying magnetic TiO₂ by silver nanoparticles, charge separation was eased by catching photo-generated electrons, resulted in an enhanced photo- and biological activity. Graphical abstract.

Keywords: Antibacterial activity; Core-shell; Dye degradation; Magnetic nanocomposite; Synthesis; TiO2 photocatalyst.