Magnetically Separable Mixed-Phase α/γ-Fe2O3 Catalyst for Photo-Fenton-like Oxidation of Rhodamine B

Abstract

Iron oxides are widely used as catalysts for photo-Fenton-like processes for dye oxidation. In this study, we report on the synthesis of an α/γ-Fe2O3 mixed-phase catalyst with magnetic properties for efficient separation. The catalyst was synthesized using glycine–nitrate precursors. The synthesized α/γ-Fe2O3 samples were characterized using scanning electron microscopy, X-ray diffraction spectroscopy (XRD), Raman shift spectroscopy, X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometer (VSM). The diffraction peaks were indexed with two phases, α-Fe2O3 as the main phase (79.6 wt.%) and γ-Fe2O3 as the secondary phase (20.4 wt.%), determined using the Rietveld refinement method. The presence of Fe2+ was attributed to oxygen vacancies. The mixed-phase α/γ-Fe2O3 catalyst exhibited remarkable photo-Fenton-like degradation performance for Rhodamine B (RhB) in neutral pH. The effects of operating parameters, including H2O2 concentration, catalyst concentration, and RhB concentration, on the degradation efficiency were investigated. The removal rates of color were 99.2% after 12 min at optimal conditions of photo-Fenton-like oxidation of RhB. The sample exhibited a high saturation magnetization of 28.6 emu/g. Additionally, the α/γ-Fe2O3 mixed-phase catalyst showed long-term stability during recycle experiments, with only a 5% decrease in activity.

Combination NIPS/TIPS Synthesis of α-Fe2O3 and α/γ-Fe2O3 Doped PVDF Composite for Efficient Piezocatalytic Degradation of Rhodamine B

“…Quantitative phase analysis using the Rietveld method showed that α-Fe 2 O 3 exists as the main phase (79.6%), while γ-Fe 2 O 3 is present in a quantity of 20.4% (see Figure S2 Supplementary File) [20,23,24,[31][32][33][34][35]. The average crystallite size of the α-phase was found to be 47.4 nm, while that of the γ-phase was 45.7 nm [29].…”

“…The synthesis of α/γ and α-Fe 2 O 3 was carried out using the combustion method of glycine-nitrate precursors [27][28][29]. An aqueous iron (III) nitrate solution was used as the starting material, and glycine was used as the fuel.…”

Electrochemical Synthesis of Superparamagnetic Fe3O4 Nanoparticles for the Photo‐Fenton oxidation of Rhodamine B

“…[25] The irradiation of Fe 2 + + H 2 O 2 , also called photo-Fenton reaction, enhances the reaction rate of oxidation organic contaminants through the generation of * OH which direct attack the organics. [26] The additional use of light in the Fenton process enhances the energy of chemical processes by promoting additional photochemical reactions, such as photo-reduction of Fe 3 + to Fe 2 + and photolytic decomposition of H 2 O 2 to * OH. [27] Homogeneous Fenton has some disadvantages, such as high efficiency only in acidic conditions and the precipitation of Fe 2 + as sludge.…”

1D/2D Electrospun Polyvinylidene Fluoride Nanofibers/Carbon Flakes Hybrid Nonmetal Polymeric Photo‐ and Piezocatalyst

“…In light of the growing problems associated with wastewater pollution and the need for renewable energy sources, heterogeneous photocatalysis is one of the most promising methods for wastewater treatment. However, photocatalysts have several drawbacks, such as limited light absorption ability, fast charge recombination, and being a source of secondary pollution [1–2] …”

“…However, photocatalysts have several drawbacks, such as limited light absorption ability, fast charge recombination, and being a source of secondary pollution. [1][2] In recent years, research has been conducted to overcome these drawbacks using photocatalysts with piezoelectric properties or their heterojunction systems, such as ZnO, [3] BaTiO 3 , [4] BiVO 4 /BiFeO 3 , [5] ZnO/ZnS/MoS 2 , [6] PbTiO 3 /CdS, [7] KNbO 3 , [8] NiO/ BaTiO 3 , [9] Bi 2 WO 6 /ZnSnO 3 , [10] Ag/Bi 5 O 7 I, [11] MoO x /ZnS/ZnO [12] etc. However, the issue of secondary pollution remains relevant, and these materials themselves are highly toxic.…”