Hierarchical Nanoflower Structure Materials Used In Dye Sensitized Solar Cell

Dye-sensitized solar cell （DSSC）, the third generation of solar cell, has attracted tremendous attention due to their cost effectiveness, environmental benignity, and ease of fabrication. Using TiO₂ nanocrystalline thin film as the photo-anode of the DSSC was successfully made. However, the pure TiO₂ nanocrystalline film has poor light utilization and frequently surface recombination. Therefore, it is necessary to develop a simple and effective method to improve the light utilization of photo-anode and reduce the surface recombination to enhance performance of DSSC.In this paper, the flower-like TiO₂ and SnO₂ were prepared from a modified method of one-step hydrothermal synthesis. The morphology, crystal shape and micro-structures of material were studied by TEM, SEM, XED and XPS. The principle of reaction and preparation technology of flower-like TiO₂ and SnO₂ were analyzed by the morphology with different reaction time. Then, we mixed flower-like TiO₂ with P25 powers and used as scattering layer of DSSC. The testing results showed better diffuse reflection ability, compared to pure P25 photo-anodes. While the decreasing of dye adsorption and surface area was little. The EIS test showed that the mix of these large particles also improves the electronic transmission speed. Finally, the efficiency of DSSC was improved.We used the flower-like SnO₂ particles in the DSSC light scattering layer, and studied the influence of scattering particle morphology to DSSC performance. Testing results showed that the flower-like SnO₂ particles as a composite of scattering particles can reduce the electronic recombination in transmission. At the same time, the completing rods have a great influence on electron transfer resistance. Finally, the DSSC fabricated with flower-like SnO₂ reached an efficiency of 6.71%.