In-Situ Probing of H2O Effects on a Ru-Complex Adsorbed on TiO2 Using Ambient Pressure Photoelectron Spectroscopy
2016 (English)In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 59, no 5-7, 583-590 p.Article in journal (Refereed) PublishedText
Dye-sensitized interfaces in photocatalytic and solar cells systems are significantly affected by the choice of electrolyte solvent. In the present work, the interface between the hydrophobic Ru-complex Z907, a commonly used dye in molecular solar cells, and TiO2 was investigated with ambient pressure photoelectron spectroscopy (AP-PES) to study the effect of water atmosphere on the chemical and electronic structure of the dye/TiO2 interface. Both laboratory-based Al K alpha as well as synchrotron-based ambient pressure measurements using hard X-ray (AP-HAXPES) were used. AP-HAXPES data were collected at pressures of up to 25 mbar (i.e., the vapor pressure of water at room temperature) showing the presence of an adsorbed water overlayer on the sample surface. Adopting a quantitative AP-HAXPES analysis methodology indicates a stable stoichiometry in the presence of the water atmosphere. However, solvation effects due to the presence of water were observed both in the valence band region and for the S 1s core level and the results were compared with DFT calculations of the dye-water complex.
Place, publisher, year, edition, pages
2016. Vol. 59, no 5-7, 583-590 p.
Dye-sensitized solar cells, AP-HAXPES, DFT, H2O, Photoelectron spectroscopy
IdentifiersURN: urn:nbn:se:uu:diva-282482DOI: 10.1007/s11244-015-0533-3ISI: 000371424800018OAI: oai:DiVA.org:uu-282482DiVA: diva2:917118
FunderSwedish Energy Agency, P22191-5Swedish Research Council, VR-2010-4132Swedish Research Council, VR-2014-6019Swedish Research Council, VR-2015-03956StandUpCarl Tryggers foundation , CTS 14:355VINNOVA