Diffusion and adsorption of dye molecules in mesoporous TiO2 photoelectrodes studied by indirect nanoplasmonic sensing
Artikel i vetenskaplig tidskrift, 2013

In this study, we used Hidden Interface-Indirect Nanoplasmonic Sensing (HI-INPS) for real time monitoring of dye impregnation (adsorption-diffusion process) of mesoporous TiO2 electrodes of the kind used in dye-sensitized solar cells. We measured the dye percolation time (i.e. the time to diffuse to the bottom of a TiO2 photoelectrode film) for dye Z907 in a 1 : 1 volume mixture of acetonitrile and tert-butanol for different dye concentrations and for different thicknesses of the TiO2 film, while the total amount of adsorbed dye was simultaneously measured by optical absorption spectroscopy. The experimental data for the impregnation process were analyzed by employing a diffusion-front model, combining diffusion and Langmuir type adsorption, which allows extraction of the effective diffusion coefficient for the system. The latter value is about 15 mu m(2) s(-1) for the combined adsorption-diffusion movement of dye molecules through the TiO2 structure, which is an order of magnitude or more smaller than that for "free" diffusion of dye molecules in bulk solvents.

TIME

N719 DYE

PERFORMANCE

SENSORS

SURFACE-PLASMON RESONANCE

EFFICIENCY

SENSITIZED SOLAR-CELLS

KINETICS

FILMS

Författare

Viktoria Gusak

Chalmers, Teknisk fysik, Kemisk fysik

Leo-Philipp Heiniger

Ecole Polytechnique Federale de Lausanne

Vladimir Zhdanov

Chalmers, Teknisk fysik, Kemisk fysik

Michael Graetzel

Ecole Polytechnique Federale de Lausanne

Bengt Herbert Kasemo

Chalmers, Teknisk fysik, Kemisk fysik

Christoph Langhammer

Chalmers, Teknisk fysik, Kemisk fysik

Energy and Environmental Sciences

1754-5692 (ISSN)

Vol. 6 3627-3636

Ämneskategorier

Atom- och molekylfysik och optik

DOI

10.1039/c3ee42352b