Graphene foam mediated FeS2/alpha-Fe2O3 composites for chloramphenicol photodegradation using persulfate activation under visible light irradiation

The creation of an effective treatment system is necessary due to the threats posed by chloramphenicol (CAP) antibiotic residue in water streams. Photocatalytic composites provide potential replacements for getting rid of such a dangerous pollutant. Here, a nanohybrid comprised of FeS2/alpha-Fe2O3 nanoparticles produced via deposition-precipitation is built with an oxygen-rich graphene foam (GF). X-ray diffraction (XRD), FT-IR spectroscopy, XPS, UV-diffuse reflectance examination, TEM microscopy, SEM-EDX, Porosimetery analysis, and Point of Zero Charge testing were used to evaluate the magnetic nanomaterials with various FeS2/alpha-Fe2O3@GF ratios, giving a thorough picture of their structure, band gap, morphology and surface chemical features. Under visible light, the material FeS2/alpha-Fe2O3@GF (1:4) quickly oxidizes CAP (k = 0.0159 min(-1), 20 ppm, pH 8.6) within only 10 min. In the composite-activated persulfate (PPS) system, holes are acknowledged as acceptable reactive species after the SO4 center dot- and (OH)-O-center dot radicals. Increased pore volume, surface area, and dimension reduction in comparison to individual counterparts, together with improved visible light absorption capabilities in the visible region, were the main causes of the CAP photodegradation enhancement on FeS2/alpha-Fe2O3@GF. In comparison to FeS2/alpha-Fe2O3 alone, the ratio of Fe2+ was twice as high in the FeS2/alpha-Fe2O3@GF composite, which improves PPS activation for CAP degradation. Using LC-MS, the intermediates of CAP photocatalytic oxidation that adhere to a pseudo first-order rate constant were discovered, and potential degradation routes were suggested along with a toxicity evaluation.