Synthesis and Application of a Fe3O4/Ag3PO4/g-C3N4 Magnetic Composite Photocatalyst for Sulfonamide Antibiotics Degradation

Abstract

In this study, a novel Fe3O4/Ag3PO4/g-C3N4 magnetic composite photocatalyst was successfully synthesized, tailored specifically for the visible light-driven photocatalytic degradation of sulfonamide antibiotics, more precisely, sulfamethazine (SMZ). To analyze the fabricated samples, characterization techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), photoluminescence spectroscopy (PL), and UV-vis diffuse reflectance spectra (UV-vis) were systematically employed. The composite showcased efficient visible-light absorption and charge separation, with its peak photocatalytic performance recorded at a solution pH value of 6.0. Significantly, the Fe3O4/Ag3PO4/g-C3N4 magnetic composite photocatalyst displayed excellent stability and recyclability, consistently maintaining a high degradation efficiency of over 97% even after five consecutive cycles. Further experimentation with radical scavengers confirmed a significant decrease in photocatalytic activity, establishing that superoxide radicals (•O2−) and photo-generated holes (h+) are the primary active species during the degradation of SMZ. Overall, it provides a crucial understanding regarding the photocatalytic decomposition of sulfonamide antibiotics using magnetic composite photocatalysts. It also emphasizes the promising potential of the Fe3O4/Ag3PO4/g-C3N4 composite for tangible applications in environmental remediation.