MWCNT/BiVO4 photocatalyst for inactivation performance and mechanism of Shigella flexneri HL, antibiotic-resistant pathogen

Abstract

In order to prepare photocatalysts that could efficiently inactivate antibiotic-resistant pathogens, multi-wall carbon nanotubes/monoclinic bismuth vanadate/tetragonal bismuth vanadate (MWCNT/M-BiVO4/T-BiVO4) photocatalysts were prepared under different pH conditions (pH = 1, 3, 5, and 7) and MWCNTs modification. The MWCNT/BiVO4 photocatalyst prepared at pH = 1 (C/BVO-1) showed the best photocatalytic response and the highest photogenerated electron-hole pair separation rate based on various characterizations. Additionally, C/BVO-1 demonstrated an excellent photocatalytic inactivation on Shigella flexneri HL, a common antibiotic-resistant pathogenic bacteria in the environment. EPR and fluorescent probe experiment indicated that C/BVO-1 had a good ability to produce •O2−, h+ and •OH for photocatalytic inactivation. A related photocatalytic inactivation mechanism against the bacteria was proposed. Finally, photocatalytic inactivation experiments of antibiotic-resistant Shigella flexneri HL in actual poultry breeding wastewater was conducted to evaluate the application potential of photocatalyst in actual wastewater. This research provides a substantial reference for the application of photocatalytic technology in the inactivation of antibiotic-resistant pathogens in livestock or poultry breeding wastewater, and provides ideas for future research on antibiotic-resistance genes (ARGs) using photocatalysis.