Fabrication of titanium incorporation into zeolitic imidazolate framework-L on fabric carrier for visible-light driven photocatalytic antibacterial activity

Abstract

The development of metal–organic frameworks (MOFs) as a nanoplatform for emerging antibacterial agents has gained great attention. In this work, TiO2 nanoparticles in-situ incorporated in zeolitic imidazolate framework-L (ZIF-L) successfully grow on the non-textile fabric substrate as a novel antibacterial composite ZIF-L@TiO2/fabric with improved visible-light driven antibacterial activity. The morphology and composition of the as-prepared antibacterial composite are characterized via SEM, TEM, XRD, and XPS analysis. The material with high light use efficiency can generate more reactive oxygen species (ROS) under light irradiation than that in dark, which suggests the synergistic effect between TiO2 nanoparticles and ZIF-L in the visible region. Correspondingly, ZIF-L@TiO2/fabric exhibits outstanding antibacterial effect against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which can also be verified by the Leica SP5 laser scanning confocal microscope (LSCM) results. Furthermore, the possible antibacterial mechanism is proposed. Under visible light irradiation, the synergy of TiO2 nanoparticles and ZIF-L is in favor of producing hydroxyl radical (·OH) and superoxide radicals (·O2−) that directly leads to the death of bacteria. The sufficient antibacterial activity of ZIF-L@TiO2/fabric (over 95% after six antibacterial assay cycles) ensures the long-term use of the material. At this point, the newly synthesized material gives new sight on preparing other MOFs based composites with photocatalytic antibacterial effect for bacterial issues.