Please use this identifier to cite or link to this item:
http://hdl.handle.net/11375/12916
Title: | Pore-size Dependence of Ion Diffusivity in Dye-sensitized Solar Cells |
Authors: | Ma, Yiqun |
Advisor: | Xu, Gu |
Department: | Materials Science and Engineering |
Keywords: | mesoporous materials;mass transport;iodide/triiodide redox couple;TiCl4 post-treatment;surface diffusion;Semiconductor and Optical Materials;Semiconductor and Optical Materials |
Publication Date: | Apr-2013 |
Abstract: | <p>The pore-size dependence of liquid diffusivity in mesopores has been a controversial topic. It is especially meaningful in dye-sensitized solar cells (DSSCs) because the triiodide ion diffusivity is closely related to the cell performance. By applying electrochemical measurements, the pore-size dependence of ion diffusivity in DSSCs was investigated based on TiO<sub>2</sub> thin films of variable pore diameters. The alternation of pore-size was achieved by the epitaxial growth of TiO<sub>2</sub> after TiCl<sub>4</sub> post-treatments. From the trend of normalized diffusivities, the respective valid regimes of pore-size dependent and independent diffusion were determined, which were separated by the transition point located at 5-7 nm. In addition, my results have showed that the DSSC fabrication processes, e.g., dye loading, TiCl<sub>4</sub> post-treatment will not lead to the transition of diffusion behaviors. Furthermore, the unexpected drop of diffusivity after one TiCl<sub>4</sub> treatment is attributed to the involvement of surface diffusion in untreated TiO<sub>2</sub> matrix.</p> |
URI: | http://hdl.handle.net/11375/12916 |
Identifier: | opendissertations/7761 8820 4039852 |
Appears in Collections: | Open Access Dissertations and Theses |
Files in This Item:
File | Size | Format | |
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fulltext.pdf | 2.48 MB | Adobe PDF | View/Open |
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