Towards molecular understanding of surface and interface catalytic engineering in TiO2/TiOF2 nanosheets photocatalytic antibacterial under visible light irradiation

TiO 2 /TiOF 2 Z-scheme nanosheets have been successfully synthesized for photocatalytic antibacterial. The antibacterial efficiency of TiO 2 /TiOF 2 against E. coli and S. aureus were 99.90 % and 81.89 % at low material concentration (110 μg/mL), respectively, which are higher than those of pure TiO 2 , TiOF 2 , and Degussa P25. In situ molecular spectroscopy results demonstrate that the microstructure of the synthesized material can be reconstructed and optimized to enhance the exposure of the active sites·H 2 O and O 2 are effectively adsorbed on the catalyst surface and activated to form OH…Ti and O…Ti surface active species. Furthermore, the dense interface formed in TiO 2 /TiOF 2 acts as an efficient transport path for photoexcited electrons from TiO 2 to TiOF 2 , and thus accelerates the formation of reactive oxygen species . Finally, the mechanism of bacterial inactivation is systematically discussed considering the main active substances, cell morphological changes, and activity of antioxidant enzymes.