The enhanced photocatalytic properties of MnO 2/g-C 3 N 4 heterostructure for rapid sterilization under visible light

J Hazard Mater. 2019 Sep 5;377:227-236. doi: 10.1016/j.jhazmat.2019.05.074. Epub 2019 May 27.

Abstract

Herein, a heterostructure based on MnO2 and g-C3N4 was constructed on the surface of metallic Ti implants, in which MnO2 favored the transfer and separation of free charges to enhance the photoconversion efficiency of g-C3N4 by 21.11%. Consequently, the yield of ROS was promoted significantly, which denatured protein and damaged DNA to kill bacteria efficiently. In addition, glutathione (GSH, l-γ-glutamyl-l-cysteinyl-glycine) defending oxidative stress in bacteria, was oxidized by MnO2 in the hybrid coating once the bacterial membrane was disrupted by ROS. Hence, after visible light irradiation for 20 min, MnO2/g-C3N4 coating exhibited superior disinfection efficacy of 99.96% and 99.26% against S. aureus and E. coli severally. This work provided a practical sterilization strategy about MnO2/g-C3N4 systems through the synergistic effects of enhanced photodynamic antibacterial therapy and oxidization effect of MnO2 with great biosafety, in which MnO2 enhanced the photocatalyst property of g-C3N4 to generate more ROS and deplete GSH to improve antibacterial efficiency. It will bring more insight into rapid and highly effective disinfection and antibacterial strategy without using traditional high-temperature, ultraviolet ray and antibiotics that cause side-effects.

Keywords: Disinfection; Heterostructure; MnO(2) nanosheet; Photocatalytic; g-C(3)N(4).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / metabolism
  • Bacteria / radiation effects
  • Catalysis
  • Cell Membrane / metabolism
  • Cell Membrane / radiation effects
  • DNA Damage
  • Escherichia coli / radiation effects
  • Glutathione / metabolism
  • Graphite / chemistry*
  • Graphite / radiation effects
  • Light
  • Manganese Compounds / chemistry*
  • Manganese Compounds / radiation effects
  • Microbial Sensitivity Tests
  • Models, Molecular
  • Nitrogen Compounds / chemistry*
  • Nitrogen Compounds / radiation effects
  • Oxides / chemistry*
  • Oxides / radiation effects
  • Photochemical Processes*
  • Reactive Oxygen Species
  • Staphylococcus aureus / metabolism
  • Staphylococcus aureus / radiation effects
  • Sterilization / methods*

Substances

  • Manganese Compounds
  • Nitrogen Compounds
  • Oxides
  • Reactive Oxygen Species
  • graphitic carbon nitride
  • manganese oxide
  • Graphite
  • Glutathione