Magnetic Fe3S4/Ti3C2 MXene composite as a high-efficiency photo-Fenton catalyst for enhanced degradation of tetracycline hydrochloride

In this study, novel magnetic Fe 3 S 4 /Ti 3 C 2 MXene composites were successfully synthesized via a hydrothermal method and employed as a highly efficient photo-Fenton catalyst for the degradation of tetracycline hydrochloride (TCH). The optimized composite (Fe 1 M 0.5 ), with a Fe 3 S 4 : Ti 3 C 2 MXene mass ratio of 1:0.5, exhibited exceptional catalytic performance under visible light, achieving a TCH removal efficiency of 93.9 % within 90 min (pH = 4.2, 10 mM H 2 O 2 , 0.3 g L −1 catalyst). The introduction of Ti 3 C 2 MXene significantly mitigated Fe 3 S 4 agglomeration, enhanced charge carrier separation, and broadened the operational pH range (2.2–7.2). Mechanistic studies revealed that the TCH degradation process was dominated by the synergistic effects of •OH, •O 2 − , h + , and e − dominated, which were facilitated by the Fe 3+ /Fe 2+ and Ti 4+ /Ti 3+ redox cycles as well as the formation of Schottky heterojunction. The composite demonstrated robust stability (>80 % TCH degradation efficiency after five cycles) and versatility in degrading diverse pollutants (e.g., RhB, MB). Magnetic characterization confirmed its easy recovery (10 emu g −1 saturation magnetization), and interference tests indicated a high tolerance to common inorganic anions (e.g., Cl − , SO 4 2− , NO 3 − ). This work highlights the potential of Fe 3 S 4 /Ti 3 C 2 MXene composites as sustainable, multifunctional catalysts for environmental remediation, offering insights into the design of MXene-based hybrid systems for advanced oxidation processes.