Fe-doped MoS2@cotton catalyst for norfloxacin degradation under low-frequency vibration: Peroxomonosulfate activation, mechanism, and reusability

Norfloxacin (NOR), a common antibiotic, generates substantial wastewater during the production process. This wastewater infiltrates lakes, rivers, and groundwater systems, giving rise to water pollution. It also poses risks of human accidental ingestion. Once entering the human body, NOR may cause damage to organisms and enhance drug resistance, thereby posing a severe threat to human health. NOR has been recognized as an emerging micro-pollutant, and traditional wastewater treatment technologies struggle to efficiently remove it. Therefore, there is an urgent need to develop an effective and environmentally friendly technology for the removal of norfloxacin from water. In this study, a reusable fabric-based highly efficient catalyst, DHCA@MoS 2 @CMCF-Fe, was developed. The research results indicate that under mild stirring conditions, the surface of DHCA@MoS 2 @CMCF-Fe can generate abundant free charges, enabling the efficient activation of peroxomonosulfate (PMS). Moreover, the exposed Mo(IV) active sites in DHCA@MoS 2 @CMCF-Fe effectively accelerate the electron transfer and redox cycle of Fe(II)/Fe(III), ensuring the continuous and efficient activation of PMS. Furthermore, the synergistic effect between MoS 2 and Fe further optimizes the electron conduction pathway, enhancing the efficiency of charge separation and transfer within the system, and enabling the continuous generation of a large number of highly reactive radicals. The degradation rate of NOR by the DHCA@MoS 2 @CMCF-Fe system can reach 95.7 %, which is 102 % higher than that of the DHCA@MoS 2 @CMCF system. In experiments exploring the effects of various inorganic anions on the degradation of NOR, it was found that Cl − and SO 4 2− had relatively minor impacts on NOR degradation. In contrast, HCO 3 − exerted a certain inhibitory effect, causing the degradation rate to decline from 95.7 % to 80 %. To elucidate the degradation mechanism of NOR, quenching experiments and electron paramagnetic resonance (EPR) spectroscopy were conducted. The results confirmed that 1 O 2 and SO 4 − · were the key reactive species dominating the degradation of NOR. Subsequently, a detailed analysis was performed to uncover the catalytic mechanism by which the DHCA@MoS 2 @CMCF-Fe system degrades NOR. Furthermore, after five cycles of reuse, the catalyst maintained high catalytic activity, with the degradation rate of NOR remaining above 85 %. Aiming at the drawbacks of traditional powder catalysts, such as difficult recovery and potential for secondary pollution, this study supported the catalyst on fabric, effectively addressing these issues to the greatest extent. This research not only opens up a new pathway for the application of PMS in the treatment of antibiotic-contaminated water but also fully demonstrates the immense application potential of DHCA@MoS 2 @CMCF-Fe in the removal of organic pollutants, providing novel ideas and directions for the development of environmental remediation technologies.