Multifunctional Z-Scheme NaGdF4:Yb,Tm@ZnO/Ag3PO4 nanoheterojunction
photocatalysts for water purification and antibacterial wound healing
Abstract
Short title of the paper …
Photocatalysts with dual functionalities of decomposing organic
pollutants in water and combating bacterial infections are increasingly
important. Herein, NaGdF4:Yb,Tm@ZnO/Ag3PO4 (UZA) nanoheterojunction
photocatalysts were synthesized via hydrothermal, sol-gel, and in situ
deposition methods. The UZA photocatalyst demonstrated exceptional
efficiency in generating reactive oxygen species (ROS), crucial for
organic pollutant degradation. The incorporation of Ag facilitated
efficient charge transfer in the all-solid-state Z-scheme
nanoheterojunction system. Furthermore, UZA exhibited potent
antibacterial properties against both Gram-positive Staphylococcus
aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). The
minimum bactericidal concentrations (MBC) of UZA were 50 μg/mL for S.
aureus and 25 μg/mL for E. coli under natural irradiation, and 100 μg/mL
for S. aureus and 25 μg/mL for E. coli under 980 nm irradiation,
respectively. In vivo studies using a mouse model of acute
bacterial-infected wounds demonstrated that UZA incorporated into
chitosan hydrogel dressings accelerated wound healing through
photodynamic therapy within 9 days. The treated wounds exhibited rapid
reduction to 9.95% of the initial area, diminished inflammatory
responses, and enhanced re-epithelialization attributed to sustained
antibacterial effects and pathogen inhibition. Moreover, UZA composites
showed excellent biocompatibility with a minimal hemolysis rate of 0.5%
on erythrocytes. These findings underscore the promising application of
UZA in water treatment for organic pollutants and in the treatment of
skin wound infections caused by pathogenic bacteria.