Novel application of FeIn2S4 as an efficient photo-Fenton catalyst for degradation of Ponceau 4R in aqueous solution

Abstract

The chalcogenide composite FeIn 2 S 4 was prepared by hydrothermal route and, for the first time, investigated as a heterogeneous catalyst in the photo-Fenton treatment for Ponceau 4R dye (C 20 H 11 N 2 Na 3 O 10 S 3 ) under visible irradiation. The composite was characterized by X-ray diffraction (DRX), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectrometry (EDS) and elemental mapping, band gap energy and X-ray photoelectron spectroscopy (XPS). The optimal experimental conditions were investigated and determined to be pH 3.0, 0.5 g L −1 of catalyst and 2.5 mmol L −1 of H 2 O 2 . A decolorization efficiency of 93.3% was achieved in 60 min of reaction and a TOC removal of 92.3% was reached in 180 min. The stability and recycle capacity of FeIn 2 S 4 indicated that the catalyst can be used more than four times without considerable loss of efficiency. Free radicals investigation revealed that • OH and O 2•− radicals were the major oxygen reactive species involved on Ponceau 4R degradation. The lower-mass intermediates from Ponceau 4R degradation were identified, and a mechanism for the photo-Fenton treatment was suggested. Therefore, the composite showed a performance that makes it a promising catalyst for removing emerging contaminants in water.

Design and Fabrication of Biomass Derived Black Carbon Modified g‐C3N4/FeIn2S4 Heterojunction as Highly Efficient Photocatalyst for Wastewater Treatment

“…In─O stretching and bending vibrations are additionally accountable for the absorption maxima at 1156 and 798 cm −1 , respectively, and exist in all xFeInS/BC‐CN samples. [ 55 ] These results show that the composite materials are successfully fabricated without the presence of any impurities. The Raman spectra (Figure 1c) of BC‐CN and 4FeInS/BC‐CN samples showed unique Raman bands.…”

“…These results are in accord with the previous studies, demonstrating a close interaction between the components of the 4FeInS/BC‐CN composite. [ 21,55 ] The EDX elemental mapping images of FeInS/BC‐CN (Figures 3g‐k) clearly reveal the homogeneous distribution of all elements implying the successful fabrication of FeInS/BC‐CN composite photocatalyst. This study demonstrates that 4FeInS/BC‐CN heterostructure effectively establishes good interfacial contact while maintaining the original structure without any obvious morphological changes.…”

“…This indicates that the as‐synthesized materials have good crystallinity and no impurity peaks. [ 55 ] The typical diffraction peaks of BC‐CN could be indexed to the standard pattern of g‐C 3 N 4 (JCPDS No. 87–1526).…”

“…The TEM image of pure FeInS (Figure 3c) shows evenly sized sheets assembled by abundant nanosheets and HR‐TEM images confirm that the lattice fringes of FeInS have the interplanar spacing of 0.46 nm (220) facet (Figure 3d). [ 55 ] The presence of lattice fringes and bending cycles shown in the SAED pattern of FeInS demonstrate that the material is highly crystalline. According to the TEM image (Figure 3e), the FeInS nanosheets are extensively incorporated into the BC‐CN sheet, providing the 4FeInS/BC‐CN composite a heterogeneous structure as opposed to a physical mixture of the two individual phases of FeInS and BC‐CN.…”

“…The atoms of transition metals may provide additional adsorptive sites and valence electrons, which would facilitate the adsorption of pollutants. [ 55 ] The absorption capacity of FeInS/BC‐CN composites is increased with the increase in content of FeInS. The exceptional characteristic of the material facilitates the collection of pollutants toward the catalytic active site, hence enabling a more efficient tendency of active species toward various pollutants.…”