|About this Abstract
||Materials Science & Technology 2012
||International Symposium on Defects, Transport and Related Phenomena
||Optical In-Situ Spectroscopy of Titania Thin Films
||Jianmin Shi, Doh-Kwon Lee, Han-Ill Yoo, Jürgen Janek, Klaus-Dieter Becker
|On-Site Speaker (Planned)
Titanium dioxide, TiO<SUB>2</SUB>, is one of the most promising photocatalysts for applications in environmental protection and renewable energies. In order to improve the photocatalytic efficiency, defect engineering of TiO<SUB>2</SUB> via reduction and/or anion doping has attracted much attention in recent years. Reduced and nitrogen-doped titanium dioxide thin films exhibit a large electronic absorbance in the visible and NIR region. Oxidation experiments of the oxygen deficient TiO<SUB>2</SUB> thin films in atmospheres of pure oxygen or nitrogen at high temperatures were performed and monitored by optical in-situ spectroscopy. The oxidation kinetics can be analyzed using a parabolic rate law yielding an activation energy of 1.96 eV. The re-oxidation kinetics and the blue shift of the band gap of nitrogen-doped thin films observed during the oxidation processes are discussed in the framework of a microscopic oxidation model and in relation to the release of nitrogen from the thin films, respectively.