Anchoring group and auxilary ligand effects on the binding of ruthenium complexes to nanocrystalline TiO2 photoelectrodes

Kristine Kilså, Elizabeth I. Mayo, Jordan Katz, Bruce S. Brunschwig, Harry B. Gray, Nathan S Lewis, Jay R. Winkler

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The thermodynamics and kinetics of binding to nanocrystalline TiO 2 were investigated for four ruthenium complexes with different numbers of possible anchoring groups and auxiliary ligands. Infrared spectroscopic data indicated that the dyes bound in a bridging mode with the oxygen atoms bound to separate titanium atoms. Complexes with only one or two anchoring groups used all of their carboxy groups to bind. Complexes having four or six linkers, used two groups in binding. The dyes yielded similar maximum coverages on TiO2, but different binding constants and desorption kinetics. The binding constant for the monocarboxy dye was lower than for the others. The adsorption rate constants were all similar, suggesting that formation of the first bond to TiO2 was rate limiting. Binding of the dyes from a buffered ethanol solution yielded lower coverages than from neat ethanol, although binding constants increased up to 100 times, indicating competition for, and/or deactivation of, TiO2 sites. For the monocarboxy dye, the integrated quantum yield was lowest, and electron transfer between TiO2 and the redox couple was most facile.

Original languageEnglish
Title of host publicationProceedings - Electrochemical Society
Pages49-63
Number of pages15
VolumePV 2004-22
Publication statusPublished - 2006
Event205th Electrochemical Society Meeting - San Antonio, TX, United States
Duration: May 9 2004May 14 2004

Other

Other205th Electrochemical Society Meeting
CountryUnited States
CitySan Antonio, TX
Period5/9/045/14/04

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ASJC Scopus subject areas

  • Engineering(all)

Cite this

Kilså, K., Mayo, E. I., Katz, J., Brunschwig, B. S., Gray, H. B., Lewis, N. S., & Winkler, J. R. (2006). Anchoring group and auxilary ligand effects on the binding of ruthenium complexes to nanocrystalline TiO2 photoelectrodes. In Proceedings - Electrochemical Society (Vol. PV 2004-22, pp. 49-63)