Xing Guan Zhao

Enhancement of the photoelectric performance of dye-sensitized solar cells using Ag-doped TiO2 nanofibers in a TiO2 film as electrode.

For high solar conversion efficiency of dye-sensitized solar cells [DSSCs], TiO2 nanofiber [TN] and Ag-doped TiO2 nanofiber [ATN] have been extended to be included in TiO2 films to increase the amount of dye loading for a higher short-circuit current. The ATN was used on affected DSSCs to increase the open circuit voltage. This process had enhanced the exit in dye molecules which were rapidly split into electrons, and the DSSCs with ATN stop the recombination of the electronic process. The conversion efficiency of TiO2 photoelectrode-based DSSCs was 4.74%; it was increased to 6.13% after adding 5 wt.% ATN into TiO2 films. The electron lifetime of DSSCs with ATN increased from 0.29 to 0.34 s and that electron recombination was reduced.

Increases in solar conversion efficiencies of the ZrO2 nanofiber-doped TiO2 photoelectrode for dye-sensitized solar cells

In this paper, in order to improve the efficiency of dye-sensitized solar cells, we introduced zirconia [ZrO2] nanofibers into a mesoporous titania [TiO2] photoelectrode. The photoelectrode consists of a few weight percent of ZrO2 nanofibers and a mesoporous TiO2 powder. The mixed ZrO2 nanofibers and the mesoporous TiO2 powder possessed a larger surface area than the corresponding mesoporous TiO2 powder. The optimum ratio of the ZrO2 nanofiber was 5 wt.%. The 5 wt.% ZrO2-mixed device could get a short-circuit photocurrent density of 15.9 mA/cm2, an open-circuit photovoltage of 0.69 V, a fill factor of 0.60, and a light-to-electricity conversion efficiency of 6.5% under irradiation of AM 1.5 (100 mW/cm2).

Preparation and Characterization of Chitosan Binder-Based Electrode for Dye-Sensitized Solar Cells

A chitosan binder-based TiO2 photoelectrode is used in dye-sensitized solar cells (DSSCs). Field-emission scanning electron microscope (FE-SEM) images revealed that the grain size, thickness, and distribution of TiO2 films are affected by the chitosan content. With addition of 2.0 wt% chitosan to the TiO2 film (D2), the surface pore size became the smallest, and the pores were fairly evenly distributed. The electron transit time, electron recombination lifetime, diffusion coefficient, and diffusion length were analyzed by IMVS and IMPS. The best DSSC, with 2.0 wt% chitosan addition to the TiO2 film, had a shorter electron transit time, longer electron recombination lifetime, and larger diffusion coefficient and diffusion length than the other samples. The results of 2.0 wt% chitosan-added TiO2 DSSCs are an electron transit time of  s, electron recombination lifetime of  s, diffusion coefficient of  cm2 s−1, diffusion length of 14.81 μm, and a solar conversion efficiency of 4.18%.

Electrochemical Properties of Dye-sensitized Solar Cells Using TiO 2 Paste Prepared by Simple Process

In this work, in order to manufacture the photoelectrode of dye-sensitized solar cells, the different anatase TiO2 paste was prepared by simple route using hydrothermal method. In comparison with the traditional preparing process, the hydrothermally synthesized TiO2 gel was used to make paste directly. Thus, the making process was simplified and the solar conversion efficiency was improved. In comparison with 5.34% solar energy efficiency of HP-1 photoelectrode, the 6.23% efficiency of HDP-1 electrode was improved by 16.67%. This is because hydrothermally synthesized TiO2 gel was used to make paste directly, the dispersibility between TiO2 particles was improved and get the smoother network, leading to the charge transport ability of the electron generated in dye molecular was improved. Further, HDP-2 photoelectrode delivered the best results with Voc (open circuit voltage), Jsc (short circuit current density) FF (fill factor) and η(solar conversion efficiency) were 0.695 V, 15.81 mA cm, 61.48% and 6.80%, respectively. In comparison with 5.34% of HP-1 photoelectrode, it was improved by 27.34%.

Electrochemical Properties of Dye-sensitized Solar Cells Using the TiO 2 Prepared by Hydrothermal Reaction

In this work, according to temperature and time of hydrothermal synthesis, the electrochemical properties of particle using TTIP based on changing temperature and time in the hydrothermal synthesis were analyzed and optimized temperature and time were derived. When hydrothermal synthesis temperature and time were and 1 h, respectively. The fabricated DSSC delivered the best electrochemical properties. In that case, particle size was 13.08 nm, electron transport time was and recombination time was . The lowest impedance of and Voc, Jsc, FF is 0.70 V, , 65.62%, respectively and corresponding efficiency of 5.34% was considered as the optimal.

Electrochemical Properties of Dye-sensitized Solar Cells with Improving the Surface Structure

We use UV(ultraviolet)- treatment to increase the surface area and porosity of films in dye-sensitized solar cells (DSSCs). After the UV- treatment, surface area and porosity of the films were increased, the increased porosity lead to amount of dye loading and solar conversion efficiency was improved. Field emission scanning electron microscopy images clearly showed that the nanocrystalline porosity of films were increased by UV- treatment. The Brunauer, Emmett, and Teller surface area of the films were increased from to by using UV- treatment for 20 min. Also, UV- treatment of films significantly enhanced their solar conversion efficiency. The efficiency of the films without treatment was 4.9%, and was increased to 5.6% by UV- treatment for 20 min. Therefore the process enhanced the solar conversion efficiency of DSSCs, and can be used to develop high sensitivity DSSCs.