Journal article

Publication year: 2009

Pages: 458-464

Journal: Electrochimica Acta

Volume number: 55

Issue number: 2

ISSN: 0013-4686

eISSN: 1873-3859

DOI Link: https://doi.org/10.1016/j.electacta.2009.08.062

Publisher: Elsevier

Abstract: 
The overall efficiency of the light-induced charge separation in dye-sensitized solar cells depends on the kinetic competition between back electron transfer and dye regeneration processes by a redox electrolyte. In a previous study, the reduction of the intermittently formed photo-oxidized dye molecules by iodide ions in the electrolyte phase was investigated using the feedback mode of a scanning electrochemical microscope (SECM) and a quantitative model had been derived. Here we provide a more thorough experimental verification of this model by variation of the excitation wavelength, light intensities and mediator concentrations. Nanoporous ZnO/Eosin Y films prepared by self-assembly were used as model electrodes and were used with an iodide/triiodide electrolyte. The experimentally found effective rate constants could be related to the rate constant for the reaction of the dissolved donor with photo-oxidized Eosin Y bound to ZnO and the absorption spectrum of the dye and confirmed the assumption made in the derivation of the model. For the regeneration process of Eosin Y, a rate constant of k(ox) with different light emitting diodes and light intensities is determined. (C) 2009 Elsevier Ltd. All rights reserved.

Harvard Citation style: Shen, Y., Tefashe, U., Nonomura, K., Loewenstein, T., Schlettwein, D. and Wittstock, G. (2009) Photoelectrochemical kinetics of Eosin Y-sensitized zinc oxide films investigated by scanning electrochemical microscopy under illumination with different LED, Electrochimica Acta, 55(2), pp. 458-464. https://doi.org/10.1016/j.electacta.2009.08.062

APA Citation style: Shen, Y., Tefashe, U., Nonomura, K., Loewenstein, T., Schlettwein, D., & Wittstock, G. (2009). Photoelectrochemical kinetics of Eosin Y-sensitized zinc oxide films investigated by scanning electrochemical microscopy under illumination with different LED. Electrochimica Acta. 55(2), 458-464. https://doi.org/10.1016/j.electacta.2009.08.062