title: Comparing the photocatalytic activity of TiO2at macro- and microscopic scales.
abstract: This study focuses on the characterization of photocatalytic TiO2coatings using Kelvin probe force microscopy. While most photocatalytic experiments are carried out at a macroscopic scale, Kelvin probe force microscopy is a microscopic technique that is surface sensitive. In order to link microscale results to macroscopic experiments, a simple method to establish the relation between Kelvin probe force microscopy and electrochemical measurements is presented by the calibration of a reference sample consisting of epitaxial deposited Cu-Ni-Au that is used as a transfer standard. The photocatalytic properties of TiO2at macro- and microscopic scales are investigated by comparing photocatalytic degradation of acetone and electrochemical experiments to Kelvin probe force microscopy. The good agreement between the macro- and microscopic experiments suggests that Kelvin probe force microscopy can be a valuable tool towards the understanding, standardization and design of TiO2-based solutions in photocatalytic applications.
authors.affiliation: DFM A/S, Danish National Metrology Institute, Matematiktorvet 307, Kongens Lyngby, DK-2800, Denmark. atr@dfm.dk.
authors.forename: Antoni
authors.identifier: http://orcid.org/0000-0002-2701-4766
authors.initials: A
authors.lastname: Torras-Rosell
authors.affiliation: DFM A/S, Danish National Metrology Institute, Matematiktorvet 307, Kongens Lyngby, DK-2800, Denmark.
authors.forename: Sabrina Rostgaard
authors.initials: SR
authors.lastname: Johannsen
authors.affiliation: DFM A/S, Danish National Metrology Institute, Matematiktorvet 307, Kongens Lyngby, DK-2800, Denmark.
authors.forename: Kai
authors.initials: K
authors.lastname: Dirscherl
authors.affiliation: Materials and Surface Engineering, Department of Mechanical Engineering, Technical University of Denmark, Produktionstorvet 425, Kongens Lyngby, DK-2800, Denmark.
authors.forename: Svava
authors.initials: S
authors.lastname: Daviðsdóttir
authors.affiliation: Tribology Centre, Danish Technological Institute, DTI, Kongsvang Allé 29, Aarhus, DK-8000, Denmark.
authors.forename: Christian Sloth
authors.initials: CS
authors.lastname: Jeppesen
authors.affiliation: Tribology Centre, Danish Technological Institute, DTI, Kongsvang Allé 29, Aarhus, DK-8000, Denmark.
authors.forename: Sascha
authors.initials: S
authors.lastname: Louring
authors.affiliation: Tribology Centre, Danish Technological Institute, DTI, Kongsvang Allé 29, Aarhus, DK-8000, Denmark.
authors.forename: Inge Hald
authors.initials: IH
authors.lastname: Andersen
mesh_terms: D002384:Catalysis; D018625:Microscopy, Atomic Force; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D014025:Titanium
keywords: Calibration; Kelvin probe force microscopy; Photocatalytic activity; Thin films; TiO2