title: Preparation and Mechanism of Cu-Decorated TiO2-ZrO2 Films Showing Accelerated Bacterial Inactivation.
abstract: Antibacterial robust, uniform TiO2-ZrO2 films on polyester (PES) under low intensity sunlight irradiation made up by equal amounts of TiO2 and ZrO2 exhibited a much higher bacterial inactivation kinetics compared to pure TiO2 or ZrO2. The TiO2-ZrO2 matrix was found to introduce a drastic increase in the Cu-dopant promoter enhancing bacterial inactivation compared to Cu sputtered in the same amount on PES. Furthermore, the bacterial inactivation was accelerated by a factor close to three, by Cu- on TiO2-ZrO2 at extremely low levels ∼0.01%. Evidence is presented by X-ray photoelectron spectroscopy for redox catalysis taking place during bacterial inactivation. The TiO2-ZrO2-Cu band gap is estimated and the film properties were fully characterized. Evidence is provided for the photogenerated radicals intervening in the bacterial inactivation. The photoinduced TiO2-ZrO2-Cu interfacial charge transfer is discussed in term of the electronic band positions of the binary oxide and the Cu TiO2 intragap state.
authors.affiliation: †Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-GPAO, Station 6, CH-1015, Lausanne, Switzerland.
authors.forename: Sami
authors.initials: S
authors.lastname: Rtimi
authors.affiliation: †Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-GPAO, Station 6, CH-1015, Lausanne, Switzerland.
authors.forename: Cesar
authors.initials: C
authors.lastname: Pulgarin
authors.affiliation: ‡Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-IPMC-LPCM, CH-1015 Lausanne, Station 3, Switzerland.
authors.forename: Rosendo
authors.initials: R
authors.lastname: Sanjines
authors.affiliation: §Institute of Chemical Physics RAS, Kosigin Str. 4, Moscow, 19991, Russia.
authors.forename: Victor
authors.initials: V
authors.lastname: Nadtochenko
authors.affiliation: ∥Université de Lausanne, IMG, Centre d'Analyse Minerale, Bat. Anthropole, CH-1015, Lausanne, Switzerland.
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Lavanchy
authors.affiliation: †Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-GPAO, Station 6, CH-1015, Lausanne, Switzerland.
authors.forename: John
authors.initials: J
authors.lastname: Kiwi
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology / Q000528:radiation effects; D003300:Copper / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects; D050296:Microbial Viability / Q000187:drug effects; D010084:Oxidation-Reduction; D010782:Photolysis; D013472:Sunlight; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction; D015040:Zirconium / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D003300:Copper; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide
keywords: Cu-doping; TiO2−ZrO2 film composites; bacterial inactivation; band gap of cosputtered TiO2−ZrO2−Cu; photocatalysis; redox catalysis