Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 60: Poster Session IV (Solid/liquid interfaces; Semiconductors; Oxides and insulators; Graphene; Plasmonics and nanooptics; Electronic Structure; Surface chemical reactions; Heterogeneous catalysis)
O 60.107: Poster
Wednesday, March 16, 2011, 17:30–21:00, P4
Conductivity of nano-porous Titania (TiO2) during UV-illumination — •Thomas Kriesche1 and Thomas Bürgi2 — 1Phys.-Chem.-Institut, Im Neuenheimer Feld 253, 69120 Uni Heidelberg — 2Faculté des Sciences, Séction de Chimie, Département de Chimie Physique, Quai Ernest-Ansermet 30, CH-1211 Genève 4
The photocatalytic property of TiO2 is used in many applications as solar cells for the production of hydrogen and electric energy, degradation of harmful substances, corrosion-protective coating. It is also investigated for energy storage (solar-to-fuel). Absorbed UV-light creates electrons and holes in the semiconductor, which recombine or can do reduction respectively oxidation on surface adsorbed molecules. The change of the conductivity during UV-irradiation reveals fundamental information about processes in nano-porous TiO2 layers. Time resolved measurements offer the possibility to combine information from other methods like infrared spectroscopy, especially ATR-FTIR in MIR range. Data from scanning-electron-microscopy is used to show the porous structures. The conductivity is measured on top of a TiO2 pill via a four point method in an Argon or Nitrogen atmosphere. It is possible to change the temperature and the humidity. For UV irradiation a Xenon lamp or 350nm diodes are in use with ∼ 0,5−1mW/cm2. The received data should be a step to describe the electron behavior of nano-porous TiO2 under UV-irradiation.