Facile fabrication of Ag/C-TiO₂nanoparticles with enhanced visible light photocatalytic activity for disinfection of Escherichia coli and Enterococcus faecalis

Abstract

This work aimed to investigate the promotive effect of Ag modification on C-TiO 2 for visible light photocatalytic disinfection of microorganisms. Ag/C-TiO 2 was prepared by a facile one-step synthesis approach through thermal oxidation of AgNO 3 -impregnated TiC precursor. The self-doped carbon exists as both interstitial and substitutional carbon to collectively enhance the visible light photocatalytic absorption. The loaded silver nanoparticles were uniformly distributed on the TiO 2 surface in the Ag 0 metallic state, further enhancing the visible light absorption due to surface plasmon resonance yet inhibiting the charge carrier recombination by conduction band electron trapping. The band structure and a tentative visible light photocatalytic disinfection mechanism of Ag/C-TiO 2 with four pathways were thus proposed, and the enhanced visible light photocatalytic performance was demonstrated for disinfection of Escherichia coli (E. coli) and Enterococcus faecalis (E. faecalis) in comparison with C-TiO 2 .This improvement was more pronounced with increasing Ag loading in the range of 0.5-5.0 wt%, which can be attributed to the improved visible light absorption and good charge carrier separation due to Ag modification as well as to the inherent bactericidal effect of metallic Ag.

Tunable and Switchable Solid State Fluorescence: Alkyl Chain Length‐Dependent Molecular Conformation and Self‐Reversible Thermochromism

“…[44,52,55] Finally, DPABM derivatives have also exhibited selective fluorescence sensing of hydrazine (10%) due to the conversion of ethylenemalononitrile to hydrazone (Figure 12, S20). [56] Polymethylmethacrylate (PMMA) polymer composites of DPABM derivatives were fabricated by adding toluene solution of DAPBM (50 mL of 10 À2 M) into toluene solution of PMMA (1 Wt%) under vigorous stirring. Drop casted film showed clear yellow or yellowgreenish fluorescence after drying.…”

Recent Developments in Fluorometric and Colorimetric Chemodosimeters Targeted towards Hydrazine Sensing: Present Success and Future Possibilities

“…Liu and coworkers [95] developed a series of AIE based probes 54-56 to detect hydrazine in DMSO/H 2 O (1/99) solution ( Figure 34). For probes 54 and 55, remarkable color changes take place from yellow to colorless, whereas 56 exhibits a dramatic color change from red to yellow in the presence of hydrazine.…”

Recent Development of Photocatalysts Containing Carbon Species: A Review

“…These results can be assigned to the coupling effect of the incorporation of carbon species and Ag nanoparticles. Ag/C-TiO 2 nanomaterials were also prepared by a one-step synthetic approach through the thermal oxidation of an AgNO 3 -impregnated TiC precursor [64]. The loaded silver nanoparticles were uniformly distributed on the TiO 2 surface in the Ag 0 metallic state, further enhancing the visible light absorption due to the surface plasmon resonance, yet inhibiting the charge carrier recombination by conduction band electron trapping.…”