Share Email Print
cover

Proceedings Paper

Ultrafast interfacial electron transfer in dye-sensitized ZnO nanocrystalline films: comparison with other metal oxides
Author(s): Akihiro Furube; Ryuzi Katoh; Kohjiro Hara; Masanori Tachiya
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Dye sensitized nanocrystalline semiconductor films are used as a photoactive part in dye-sensitized solar cells, which are recently attracting much interest both in basic and applied studies. Electron transfer reaction from a photoexcited dye molecule, which is chemically adsorbed on the surface of semiconductor, into the semiconductor conduction band is the primary step to generate photocurrent. Ultrafast pump-probe spectroscopy with a <100 fs time resolution and in a visible-to-IR wavelength range was used to elucidate the interfacial electron transfer mechanism in dye-sensitized nanocrystalline metal oxide films of ZnO, TiO2, and others. We found two types of reaction paths; one is direct electron transfer from the excited molecule to the conduction band and the other is stepwise transfer through an intermediate, which was assigned to a charge transfer complex formed by the excited molecule and a surface state on the semiconductor. The order of the observed electron transfer rates for different semiconductors was qualitatively explained by the idea of the density of electron acceptor states; that is, the larger the density of states near the energy level of the excited molecules was, the faster the electron transfer took place.

Paper Details

Date Published: 13 April 2005
PDF: 12 pages
Proc. SPIE 5725, Ultrafast Phenomena in Semiconductors and Nanostructure Materials IX, (13 April 2005); doi: 10.1117/12.586389
Show Author Affiliations
Akihiro Furube, National Institute of Advanced Industrial Science and Technology (Japan)
Ryuzi Katoh, National Institute of Advanced Industrial Science and Technology (Japan)
Kohjiro Hara, National Institute of Advanced Industrial Science and Technology (Japan)
Masanori Tachiya, National Institute of Advanced Industrial Science and Technology (Japan)


Published in SPIE Proceedings Vol. 5725:
Ultrafast Phenomena in Semiconductors and Nanostructure Materials IX
Kong-Thon Tsen; Jin-Joo Song; Hongxing Jiang, Editor(s)

© SPIE. Terms of Use
Back to Top