Magnetically Recoverable Multifunctional MoS₂ Composite Nanosheets for Water Disinfection and Purification with High Efficiency

Abstract

Due to the complexity of the actual polluted water components, the development of efficient and economical multifunctional materials has great significance and value in the remediation of polluted water. In this study, we have employed MoS 2 nanosheets as a carrier to sequentially load magnetic Fe 3 O 4 and ZnO nanoparticles via the electrostatic interaction, yielding a three-in-one MoS 2 /Fe 3 O 4 /ZnO (MFZ) composite nanosheet. The prepared MFZ could catalyze the conversion of H 2 O 2 into hydroxyl radicals ( • OH), induce intracellular oxidative stress in situ by nanosized ZnO or Zn 2+ , and produce photonic hyperpyrexia to promote the catalytic generation of • OH. In vitro antibacterial assays demonstrated that MFZ had high-performance multimodal elimination against Escherichia coli and Staphylococcus aureus in the presence of H 2 O 2 and an 808 nm laser. Moreover, MFZ could also catalyze the rapid degradation of organic pollutants in water including tetracycline (TC), methylene blue (MB), Congo red (CR), methyl orange (MO), and rhodamine B (RhB), which was mainly attributed to the strong oxidization of • OH. Not surprisingly, MFZ displayed satisfactory capacity for killing pathogenic bacteria and removing organic pollutants in real polluted water samples, and importantly, the MFZ could be efficiently recovered by applying an external magnetic field. Therefore, the magnetically recoverable MFZ composite nanomaterial proposed in this work is a versatile and sustainable alternative for future water disinfection and purification.