title: PbO-modified TiO2 thin films: a route to visible light photocatalysts.
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.
authors.affiliation: Materials Chemistry Centre, Department of Chemistry, University College London , 20 Gordon Street, London WC1H 0AJ, U.K.
authors.forename: Davinder S
authors.initials: DS
authors.lastname: Bhachu
authors.forename: Sanjayan
authors.initials: S
authors.lastname: Sathasivam
authors.forename: Claire J
authors.initials: CJ
authors.lastname: Carmalt
authors.forename: Ivan P
authors.initials: IP
authors.lastname: Parkin
mesh_terms: D002384:Catalysis; D007854:Lead / Q000737:chemistry*; D008027:Light; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D055668:Photochemical Processes; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D010087:Oxides; C009495:titanium dioxide; D007854:Lead; C047365:lead oxide; D014025:Titanium