Photoelectric Conversion Properties of Dye-Sensitized Solar Cells Using Dye-Dispersing Titania

Abstract

The time-resolved fluorescence and photoelectrochemical properties of dyesensitized solar cells using crystalline titania electrodes coated with N3 dye-dispersing amorphous titania gel were investigated to clarify the influence of the dye−titania interaction and electron transfer on their photoelectric conversion performance. The photocurrent quantum efficiency of the electrodes was remarkably increased by a steam treatment due to the crystallization and densification of the amorphous titania layer compared to that of the untreated electrode. The electron injection from the dye to the crystalline titania foundation via the steam-treated titania dispersing the dye was confirmed to be more efficient than that in the conventional electrodes. The dye-dispersing titania layer prevented interaction between the dye molecules and back electron transfer from the titania to the electrolyte. The charge separation and photoelectric conversion performance of the dye-sensitized solar cells were improved by forming the specific dye-dispersing titania layer.

Influence of dye dispersion on photoelectric conversion properties of dye-containing titania electrodes

“…35−41 The dye molecules in such materials exhibit a more efficient absorption and electron injection because they are finely dispersed in the amorphous or nanosized crystalline matrices compared to the conventional dye-adsorbed materials. 37,39,40 In this study, the dye-dispersing titania electrodes were prepared from the dye-containing titanium alkoxide sols by a room temperature sol−gel process and steam treatment at 110°C.…”

Reaction in photofuel cells using allophane–titania nanocomposite electrodes

“…The shape of all the spectra was similar to the absorption spectra of titania exhibiting the absorption edge at around 400 nm. This indicated that the photocurrent was generated by the excited electrons in the titania [31,32]. Figure 4 shows the I-V curves of the electrode observed under the same conditions.…”

Interaction between dye and zinc in the dye-dispersing ZnO films prepared by a wet process

“…The compounds in such materials exhibit a more efficient light harvesting and fluorescence because they are finely dispersed in the amorphous or nanosized crystalline matrices compared to the conventional dye-adsorbing materials [20][21][22][23]. Therefore, it is expected that such films exhibit a higher function, stability, and performance in various applications.…”

“…The organic dye-dispersing titania gel is suited for the dye-titania complex formation because the dye molecules with carbonyl and/or carboxyl groups are encapsulated in the narrow spaces of the gel [20][21][22][23][24][25][26]. The xanthene dye-dispersing titania gel was prepared without heating from a titanium alkoxide sol containing the dye molecules by the sol-gel method [27][28][29][30][31].…”

“…Xanthene dyes as laser dyes are available materials for utilizing photoenergy due to their high absorption and fluorescence efficiencies in various visible light regions [32]. It was reported that the hydrothermal treatment of a dye-dispersing amorphous titania film remarkably improved the photoelectric conversion efficiency due to not only its crystallization but also the dye-titanium complex formation [20][21][22][23][24][25][26][27][28][29][30][31].…”