PbO-modified TiO2 thin films: a route to visible light photocatalysts

Langmuir. 2014 Jan 21;30(2):624-30. doi: 10.1021/la4038777. Epub 2014 Jan 6.

Abstract

PbO clusters were deposited onto polycrystalline titanium dioxide (anatase) films on glass substrates by aerosol-assisted chemical vapor deposition (AACVD). The as-deposited PbO/TiO2 films were then tested for visible light photocatalysis. This was monitored by the photodegradation of stearic acid under visible light conditions. PbO/TiO2 composite films were able to degrade stearic acid at a rate of 2.28 × 10(15) molecules cm(-2) h(-1), which is 2 orders of magnitude greater than what has previously been reported. The PbO/TiO2 composite film demonstrated UVA degradation of resazurin redox dye, with the formal quantum yield (FQY) and formal quantum efficiency (FQE) exceeding that of a TiO2 film grown under the same conditions and Pilkington Activ, a commercially available self-cleaning glass. This work correlates with computational studies that predicted PbO nanoclusters on TiO2 form active visible light photocatalysts through new electronic states through PbO/TiO2 interfacial bonds resulting in new electronic states above the valence band maximum in TiO2, shifting the valence band upward as well as more efficient electron/hole separation with hole localization on PbO particles and electron on the TiO2 surface.

MeSH terms

  • Catalysis
  • Lead / chemistry*
  • Light*
  • Oxides / chemistry*
  • Particle Size
  • Photochemical Processes
  • Surface Properties
  • Titanium / chemistry*

Substances

  • Oxides
  • titanium dioxide
  • Lead
  • lead oxide
  • Titanium