Influence of Modification of Counter Electrode on PhotoelectricProperties of Dye-sensitized TiO_2 Solar Cells

A dye-sensitized nanocrystalline TiO 2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performance when the electrode was modified by platinum than by nickel and carbon. The influence of the incidence light wavelength on the incidence monochromatic photoelectric conversion efficiency(IPCE) was investigated. The result shows that the IPCE mainly depends on the short-circuit current density(I SC) of a DYSC, and the IPCE reaches 48.32% under the irradiation with the wavelength of 560 nm when the counter electrode of a DYSC was modified by platinum. The influence of incident light intensity on the photoelectric properties of a DYSC was also investigated. It was found that the I SC and open-circuit voltage(V OC) increased and the fill factor(f f) of the DYSC decreased with the increase of the incident light intensity.

Preparation and performance of dye-sensitized solar cells based on ZnO-modified TiO_2 electrodes

The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage （Voc） and fill factor （if） of the cells were improved sig- nificantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and fiat band potential （Vfb） were investigated. It is found that the interface charge recombination impedance increases and Vfb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO2 film.

Composite Electrode SnO_2/TiO_2 for Dye-Sensitized Solar Cells

Composite nanoporous electrode SnO2/TiO2 was fabricated for the dye sensitized solar cell (DSSC) with N3 (Cis-Ru). After introducing of TiO2, the open-circuit photovoltage (Voc) was higher than that of the pure SnO2 electrode, while short-circuit photocurrent (Isc) was varied with the ratio of the TiO2. Appropriate content of the TiO2 can be beneficial to the efficiency of the solar cell, and it gives negative impact on the composite electrode when the content of TiO2 is higher.

Photovoltaic Properties of CdSe Quantum Dot Sensitized Inverse Opal TiO₂Solar Cells: The Effect of TiCl₄Post Treatment

Recently, semiconductor quantum dot (QD) sensitized solar cells (QDSSCs) are expected to achieve higher conversion efficiency because of the large light absorption coefficient and multiple exciton generation in QDs. The morphology of TiO2 electrode is one of the most important factors in QDSSCs. Inverse opal (IO) TiO2 electrode, which has periodic mesoporous structure, is useful for QDSSCs because of better penetration of electrolyte than conventional nanoparticulate TiO2 electrode. In addition, the ordered three dimensional structure of IO-TiO2 would be better for electron transport. We have found that open circuit voltage Voc of QDSSCs with IO-TiO2 electrodes was much higher (0.2 V) than that with nanoparticulate TiO2 electrodes. But short circuit current density Jsc was lower in the case of IO-TiO2 electrodes because of the smaller surface area of IO-TiO2. In this study, for increasing surface area of IO-TiO2, we applied TiCl4 post treatment on IO-TiO2 and investigated the effect of the post treatment on photovoltaic properties of CdSe QD sensitized IO-TiO2 solar cells. It was found that Jsc could be enhanced due to TiCl4 post treatment, but decreased again for more than one cycle treatment, which indicates excess post treatment may lead to worse penetration of electrolyte. Our results indicate that the appropriate post treatment can improve the energy conversion efficiency of the QDSSCs.

后处理对TiO_2纳米晶膜电极光电性能的改善(英文)

利用TiCl4 水溶液处理TiO2 纳米晶膜电极 ,可以提高光电流 ,改善电极的光电转换性能 .对未经处理和处理后电极的比表面、孔分布 ,以及瞬态光电流分析表明 ,后处理改善了电荷在电极中的传输 。

Improving photoelectrochemical activity of dye sensitized solar cell by a bilayered electrode with an overlayer of mesoporous anatase TiO_2

For better performance of dye sensitized solar cells （DSSCs）, a bilayer structured electrode was constructed by employing a mesoporous anatase TiO2 overlayer above a commercial P25 TiO2 nanoparticles underlayer. The mesoporous anatase TiO2, prepared through a facile surfactant-assisted sol-gel process, possessed large pore size and well inter-connected network structure, both beneficial for dye adsorption and electron transfer. The dye adsorption capability of the mesoporous TiO2 was nearly twice that of the P25 counterpart. In the electrode, the mesoporous TiO2 film enhanced both dye adsorption and lightharvest, to increase photocurrent （Jsc） from 12.32 to 14.78 mA/cm^2. Compared to the single P25 TiO2 film, the synergy of the mesoporous TiO2 and the P25 TiO2 nanoparticle films in the electrode resulted in a 24% improvement in light-to-electricity conversion efficiency （η）. This bilayered electrode provides an alternative approach for further developing a photovoltaic device with better cell performance.

A Dye-sensitized Nanocrystalline Solid State Photovoltaic Cell

A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3Py+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer.