0
SOLAR ENERGY R&D IN ASIA

# Influence of Dye Adsorption Solvent on the Performance of a Mesoporous $TiO2$ Dye-Sensitized Solar Cell Using Infrared Organic Dye

[+] Author and Article Information
Takahiko Ono, Takeshi Yamaguchi

Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, 12-1, Ichigaya-funagawara, Shinjuku, Tokyo 162-0826, Japan

Hironori Arakawa

Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, 12-1, Ichigaya-funagawara, Shinjuku, Tokyo 162-0826, Japanarakawa@ci.kagu.tus.ac.jp

J. Sol. Energy Eng 132(2), 021101 (Apr 05, 2010) (7 pages) doi:10.1115/1.4001171 History: Received February 25, 2009; Revised July 22, 2009; Published April 05, 2010; Online April 05, 2010

## Abstract

The influence of a dye adsorption solvent of an infrared organic dye (NK-6037) on solar cell performance was investigated in a mesoporous $TiO2$ dye-sensitized solar cell (DSC). Various types of alcohols and a mixture of ethanol and tertiary-butanol (t-butanol) were applied as dye adsorption solvents. It was confirmed that the species of dye adsorption solvent significantly influences the performance of a DSC. Decreasing the specific dielectric constant of the dye adsorption solvent caused the amount of dye adsorbed on the $TiO2$ photoelectrode to increase dramatically. It is suggested that the specific dielectric constant of the dye adsorption solvent influences the solvation state of the NK-6037 dye in the solvent, thus determining, for instance, whether the dye is in the monomer state or the aggregate state. Interestingly, solar cell performance was not linearly proportional to the adsorbed amount of dye but a precise optimum amount of adsorbed dye was required for the best performance of the DSC. The optimum amount of adsorbed dye was approximately $5.0×10−8 mol/cm2$ and it was obtained by using solvents having a dielectric constant of approximately 18. This condition was realized by 1-butanol, 2-propanol, and a mixture of ethanol and t-butanol with a volume ratio of 7:3. The best efficiency obtained for the DSC was 1.7%, using the optimum amount of the adsorbed infrared dye NK-6037. It is speculated that an excess of dye on the $TiO2$ photoelectrode accelerates the formation of H-type dye aggregates, resulting in a decrease in short circuit photocurrent $(Jsc)$ by unfavorable side reactions of electron loss. It is demonstrated that dye adsorption solvent selection is the critical factor in obtaining high performance in a DSC

<>

## Figures

Figure 1

Molecular structure of the infrared organic dye NK-6037

Figure 2

Absorption and emission spectra of NK-6037 dye in ethanol and the absorption spectrum (light harvest efficiency) of the adsorbed NK-6037 dye over the TiO2 photoelectrode

Figure 3

Frontier molecular orbitals of the HOMO and LUMO of the infrared organic dye NK-6037 obtained by simulation using DFT on GGA-BLYP functional

Figure 4

Absorption spectra of the infrared organic dye NK-6037 in different alcoholic solutions

Figure 5

Correlation between the adsorbed amount of dyes over the TiO2 photoelectrode and the specific dielectric constant of the various dye adsorption solvents

Figure 6

LHE spectra of the adsorbed infrared organic dye NK-6037 over the TiO2 photoelectrode prepared by various kinds of alcoholic dye adsorption solvent

Figure 7

Correlation between the adsorbed amount of dyes over the TiO2 photoelectrode and Jsc, Voc, ff, and η of a DSC prepared using different single alcoholic dye adsorption solvents

Figure 8

IPCE action spectra of a DSC prepared using different single alcoholic dye adsorption solvents

Figure 9

Nyquist plots of DSCs prepared by using different single alcoholic dye adsorption solvents

Figure 10

Correlation between the adsorbed amount of dye over the TiO2 photoelectrode and the specific dielectric constant of the mixture of dye adsorption solvents composed of ethanol and t-butanol with different mixing ratios

Figure 11

Correlation between the adsorbed amount of dye over the TiO2 photoelectrode and Jsc, Voc, ff, and η of a DSC prepared using a mixture of dye adsorption solvents composed of ethanol and 1-butanol with different mixing ratios

Figure 12

IPCE action spectra of a DSC prepared using a mixture of dye adsorption solvents composed of ethanol and t-butanol with different mixing ratios

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related Proceedings Articles
Related eBook Content
Topic Collections