Influences of cation charge density on the photovoltaic performance of dye-sensitized solar cells: lithium, sodium, potassium, and dimethylimidazolium.
نویسندگان
چکیده
We investigate the dependence of the photovoltaic performance of dye-sensitized solar cells on the cations with different charge densities, such as lithium (Li(+)), sodium (Na(+)), potassium (K(+)), and dimethylimidazolium (DMI(+)). The efficiencies of light harvesting, electron injection and charge collection were evaluated to clarify the influence of cation selection on photocurrent generation. It is found that the short-circuit photocurrents of DSCs gradually diminish with decreasing cation charge densities, partially owing to reduced electron injection rates which are intimately related to the reaction Gibbs free energies. Further experiments indicate that the upward movement of conduction band edge results in decreased reaction Gibbs free energy of electron injection from Li(+) to DMI(+). At an irradiation of 100 mW cm(-2) AM1.5 sunlight, the open-circuit photovoltage and the fill factor of a typical dye-sensitized solar cell increase in the order of Li(+) < Na(+) < K(+) < DMI(+). Analyses of impedance data reveal that the increase of cell photovoltage mainly correlates with the upward shift of the conduction band edge induced by the adsorption of low-charge-density cations on the surface of titania nanocrystals. A J-V model was proposed to understand the improvement of the fill factor. It is found that the increase of the fill factor stems from the decrease of recombination current density under the equilibrium state in the dark by fitting the J-V data with the model.
منابع مشابه
Application of azo dye as sensitizer in dye-sensitized solar cells
An azo dye used as photosensitizers in Dye-sensitized solar cells DSSCs. Azo dyes economically superior to organometallic dyes because they are color variation and cheap. The spectrophotometric evaluation of an azo dye in solution and on a TiO2 substrate show that the dye form J-aggregation on the nanostructured TiO2 substrate. Oxidation potential measurements for used azo dyes ensured an energ...
متن کاملFabrication of Novel High Potential Chromium-Doped TiO2 Nanoparticulate Electrode-based Dye-Sensitized Solar Cell (DSSC)
In the current study, pure TiO2 and Cr-doped TiO2 (Cr@TiO2) nanoparticles were synthesized via sol-gel method and the resulting materials were applied to prepare the porous TiO2 electrodes for dye-sensitized solar cells (DSSCs). It is hypothesized that the advantages of the doping of the metal ions into TiO2 lattice are the temporary rapping of the photogenerated electron-hole (charge carriers)...
متن کاملAcid azo dyes for efficient molecular photovoltaic: study of dye-sensitized solar cells performance
In this paper we sensitized three free-metal azo days Dye 1, Dye 2 and Dye 3 based on 1,8-naphthalimide with n-propyl as the electron donor group. We used sulfonic acid and hydroxyl substituents as the electron acceptor anchoring group in synthesized dyes. The proposed dyes were sensitized from acenaphthene as the starting material by standard reactions and characterized by different techniques...
متن کاملPhotovoltaic Performance of Dye-Sensitized Solar Cell (DSSC) Fabricated by Silver Nanoclusters-Decorated TiO2 Electrode via Photochemical Reduction Technique
In this investigation, Ag@TiO2 nanocomposite was prepared by deposition of silver nanoclusters onto commercial TiO2 nanoparticles (known as P25 TiO2) via photodeposition technique as clean and simple photochemical route. The synthesized Ag@TiO2 nanocomposite was utilized in the fabrication of dye-sensitized solar cell (DSSC) chiefly because, compared ...
متن کاملInvestigation of Photovoltaic Properties of 1,8-Naphthalimide Dyes in Dye-sensitized Solar Cells
In this paper we selected two metal-free dyes (Dye 1 and Dye 2) based on 1,8-naphthalimide. The proposed dyes were sensitized from acenaphthene as the starting material by standard reactions. Spectrophotometric measurements of the organic dyes in DMF and on TiO2 substrate were carried out in order to assess changes in the status of the dyes. Maximum absorption wavelengths for Dye...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical chemistry chemical physics : PCCP
دوره 13 32 شماره
صفحات -
تاریخ انتشار 2011