Removal of Phenol Dyes Using a Photocatalytic Reactor with SnO2/Fe3O4Nanoparticles

SnO2–Fe3O4 nanocomposites for the photodegradation of the Congo red dye

Synthesis of SnO₂–Fe₃O₄ nanocomposites was conducted. The purpose of this study was to obtain the SnO₂–Fe₃O₄ nanocomposites, the effectiveness of photodegradation Congo red by SnO₂–Fe₃O₄ nanocomposites and determine the kinetics of photodegradation. The XRD analysis showed that the SnO₂–Fe₃O₄ nanocomposite best mass ratio was 1:1 based on the highest intensity of characteristic angle (2θ), which is 26.54° and had the smallest crystal size, which is 9.662 nm. Based on the UV-Vis DRS result, the SnO₂–Fe₃O₄ nanocomposites bandgap value was 2.3 eV. The magnetization saturation value of SnO₂–Fe₃O₄ nanocomposites was 64.96 emu/g. The morphology of SnO₂–Fe₃O₄ nanocomposites showed by the TEM image, where the dark spots spread in the lighter areas. The surface of SnO₂–Fe₃O₄ nanocomposites characterized by SEM with the result was bumpy surface and many pores. The EDS result of SnO₂–Fe₃O₄ nanocomposites confirmed the presence of Fe, Sn, and O elements. The functional group of SnO₂–Fe₃O₄ nanocomposites showed by FTIR data, the stretch band of Sn–O characteristics showed at wavenumber 590 cm⁻¹, and the stretch band of Fe–O showed at wavenumber 563 cm⁻¹. The optimum condition of nanocomposites at a contact time of 90 min and the optimum concentration of 18 mg/L showed that the percent of photodegradation was 50.76%. The photodegradation rate of SnO₂–Fe₃O₄ was fitted to Pseudo-second-order.

Photocatalytic activity of SnO2/Fe3O4 nanocomposites and the toxicity assessment of Vigna radiata, Artemia salina and Danio rerio in the photodegraded solution

The study was undertaken to design SnO₂/Fe₃O₄ nanocomposite by sonochemical method and to assess the photodegradation of organic dye. Textural, composition and structural features of the bare SnO₂ and SnO₂/Fe₃O₄ samples were characterized using scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The X-ray diffraction of as-synthesized SnO₂/Fe₃O₄ nanocomposites confirms the presence of tetragonal and cubic structure. The results disclose that the incorporation of Fe₃O₄ in SnO₂ decrease the crystallite size and increase the surface area compared with bare SnO₂ nanoparticle. The as-prepared photocatalyst shows higher efficiency than the bare SnO₂ under sunlight irradiation. Vigna radiata seeds (VR), Artemia salina (AS) and Zebra fish (Danio rerio (DR) were used to check the toxicity level of the treated and untreated Rhodamine B (RhB) dye solution. These models displayed good consistency for examining the harmfulness of the solutions. The results suggests SnO₂/Fe₃O₄ nanocomposite exhibited a good efficacy in the dye wastewater treatment. Further, the degradation efficiency was confirmed by the toxicity examination.