Electrochemistry, photoelectrochemistry and photoelectron spectroscopy of nanostructured metal oxides
1997 (English)Doctoral thesis, comprehensive summary (Other academic)
Dye-sensitized nanostructured metal oxides are promising materials for solar energy conversion in photoelectrochemical solar cells. For nanostructured TiO2 electrodes, photocurrents were used to study the electron transport. In both steady state and time resolved measurements, the photocurrents could be described by diffusion of electrons.
An organic ruthenium complex is presently used as light absorber in the dye sensitized solar cell. The valence band structure of the dye and dye-sensitized TiO2 electrodes were studied by means of photoelectron spectroscopy.
Electrochemical preparation combined with electron spectroscopy is generally difficult to accomplish due to the vapor pressure of the solvent. A novel device for electrochemical preparations inside the vacuum system of the preparation chamber of an electron spectrometer is described. By means of this device, the electrochemical preparations are made in a controlled atmosphere, excluding any contact to air. Using this technique, electrochemical features of proton intercalation in WO3 were related to changes in the electronic structure.
Nanostructured TiO2 (anatase) electrodes are promising as a pole in lithium ion intercalation batteries. The dynamics of the intercalation was studied with ordinary electrochemical measurements. The chemical diffusion constant, activation energy, and standard rate constant, were determined. Changes in the electronic structure were followed with photoelectron spectroscopy, which shows that intercalation of lithium into TiO2 leads to a formal reduction of Ti4+ to Ti3+.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis , 1997. , 41 p.
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-232X ; 265
Research subject Physics
IdentifiersURN: urn:nbn:se:uu:diva-834ISBN: 91-554-3931-4OAI: oai:DiVA.org:uu-834DiVA: diva2:171135
1997-03-21, the Svedberg Lecture Hall, Institute of Chemistry, Uppsala University, Uppsala, 13:15