Pt deposited TiO2 films with exposed {001} facets for photocatalytic degradation of a pharmaceutical pollutant

TiO2 films with exposed {0 0 1} facets and uniform Pt nanoparticles on the crystal facets were fabricated on a Ti substrate using a simple low temperature electrostatic self-assembly method. Proper Pt colloidal pH value was selected by determining potential of Pt NPs and TiO2 film with exposed {0 0 1} facets. Ultra high-resolution FESEM observation shows that Pt NPs with diameter of 2-4 nm were physically separated and dispersed on TiO2 facets. The Pt NPs were found to be apt to deposit on the {1 0 1} facet with more positive surface potential of TiO2 film and the mean size and the number density of Pt NPs on different facet could be rationally tailored by controlling immersion time of TiO2 film with exposed {0 0 1} facets. The Pt-TiO2 film with exposed {0 0 1} facets prepared at immersion time of 5 min shows considerably higher UV photocatalytic activity than TiO2 film with exposed {0 0 1} facets and single UV irradiation for all the experimented initial ethenzamide concentrations, and also no deactivation was observed during 3 recyling runs. The UV photocatalysis employing Pt-TiO2 film with exposed {0 0 1} facets as photocatalyst shows significant potential for application in degradation of pharmaceutical and personal care products (PPCPs) with amide bonds. (C) 2015 Elsevier B.V. All rights reserved.