Dye-sensitized solar cells; TiO2; Templating; Pore filling; Rutherford backscattering spectroscopy
Abstract :
[en] Mesoporous anatase thin films are very promising materials to act as electrode in dye-sensitized solar cells. Randomly oriented nanocrystalline TiO2 particles are usually used to prepare photoelectrodes with a thickness of 10-15 µm.
However, in solid-state DSSCs, TiO2 films thickness is limited to few µm allowing the adsorption of only a low quantity of photoactive dye and thus leading to a poor light harvesting and low conversion efficiencies.
In order to overcome this limitation, templated-assisted dip-coating techniques are used to obtain thin films with high surface area. Moreover, templating is expected to improve the pore accessibility what would promote the solid electrolyte penetration inside the porous network, making possible efficient charge transfers. In this study, films prepared from different structuring agents are discussed in terms of microstructure properties (porosity, crystallinity) and impact on the dye loading and solid electrolyte filling. As-obtained templated films have been compared to nanocrystalline films prepared by doctor blade or screen printing as reference. Different techniques such as transmission electron microscopy (TEM), atmospheric poroellipsometry (AEP) and UV-visible absorption spectroscopy (UV-vis.) have been used to describe the microstructural features of the films. Solid electrolyte infiltration has been extensively investigated by Rutherford Backscattering Spectroscopy (RBS).
Finally, templated films were evaluated as photoelectrode in solid-state DSSCs and compared to nanoparticles layers.
Disciplines :
Chemistry
Author, co-author :
Dewalque, Jennifer ; Université de Liège - ULiège > Département de chimie (sciences) > LCIS - GreenMAT
Colson, Pierre ; Université de Liège - ULiège > Département de chimie (sciences) > LCIS - GreenMAT