Ag loaded WO3 nanoplates for efficient photocatalytic degradation of sulfanilamide and their bactericidal effect under visible light irradiation

J Hazard Mater. 2016 Nov 15:318:407-416. doi: 10.1016/j.jhazmat.2016.06.066. Epub 2016 Jul 1.

Abstract

Sulfonamides (SAs) are extensively used antibiotics and their residues in the water bodies propose potential threat to the public. In this study, degradation efficiency of sulfanilamide (SAM), which is the precursor of SAs, using WO3 nanoplates and their Ag heterogeneous as photocatalysts was investigated. WO3 nanoplates with uniform size were synthesized by a facile one step hydrothermal method. Different amount of Ag nanoparticles (Ag NPs) were loaded onto WO3 nanoplates using a photo-reduction method to generate WO3/Ag composites. The physio-chemical properties of synthesized nanomaterials were systematically characterized. Photodegradation of SAM by WO3 and WO3/Ag composites was conducted under visible light irradiation. The results show that WO3/Ag composites performed much better than pure WO3 where the highest removal rate was 96.2% in 5h. Ag as excellent antibacterial agent also endows certain antibacterial efficiency to WO3, and 100% removal efficiency against Escherichia Coli and Bacillus subtilis could be achieved in 2h under visible light irradiation for all three WO3/Ag composites synthesized. The improved performance in terms of SAM degradation and antibacterial activity of WO3/Ag can be attributed to the improved electron-hole pair separation rate where Ag NPs act as effective electron trapper during the photocatalytic process.

Keywords: Bactericidal effect; Photocatalysis; Sulfanilamide; Tungsten trioxide.

MeSH terms

  • Anti-Bacterial Agents / metabolism*
  • Bacillus subtilis / drug effects
  • Bacteria / drug effects*
  • Bacteria / radiation effects*
  • Biodegradation, Environmental
  • Catalysis
  • Escherichia coli / drug effects
  • Hydrogen-Ion Concentration
  • Light
  • Nanostructures
  • Oxides / chemistry*
  • Photochemical Processes
  • Photolysis
  • Silver / chemistry*
  • Sulfanilamide
  • Sulfanilamides / chemistry*
  • Sulfanilamides / metabolism*
  • Sulfanilamides / radiation effects
  • Temperature
  • Tungsten / chemistry*

Substances

  • Anti-Bacterial Agents
  • Oxides
  • Sulfanilamides
  • Sulfanilamide
  • Silver
  • tungsten oxide
  • Tungsten