Preparation And Performance Study On Photoanode Of Dye-sensitized Solar Cells

With the rapid development of the global economy and the improvement of human living standards, human energy demand is growing. But the traditional energy sources, such as oil,gas, coal and the like, have been unable to meet the sustainable of human demand for energy due to their limited reserves, mining process of serious pollution and other factors. Hence, the development of clean energy is an important way to solve the energy demand. Solar energy is a kind of inexhaustible clean energy, has great value for development, caused the wide attention of many researchers. The dye sensitized solar cell（DSSC） with its low cost, simple production process and the advantage of very stability, has good application prospect in the process about the sun energy development and utilization.In the typical sandwich structure, photoanode as a key part of DSSCs which is not only can loading dye molecules and transporting carriers, but also as a medium which can scattering incident light, therefore, it is required to has large specific surface area, good electron transfer ability and the proper microstructure. At present, TiO₂ nanostructures is the most studied, best performance and the most widely used in photoanode of DSSC. In order to improve the photoelectric performance of DSSC, the pohotoanode structure design and TiO₂ morphology control have become a hot research topic in this field. In this paper to improve the photoelectric performance of DSSC, a novel photoanode has been designed and the relationship between different morphologies TiO₂ scattering layer and photoelectric performance of DSSC has been studied. The main research connects are as follows:1. Ultrathin two-dimensional（2D） TiO₂ nanostructures with a thickness of ⁵ nm were synthesized by a hydrothermal process. The 2D TiO₂ nanostructures and P25 nanoparticles were introduced as scattering layer and underlayer to construct a bi-layer photoanode in a dye-sensitized solar cell（DSSC）. The structure, pore size distribution and specific surface area, morphology of the as-prepared TiO₂ have been charactered by X-ray diffraction（XRD）,nitrogen adsorption desorption instrument, field emission scanning electron microscopy（FESEM）, transmission electron microscopy（TEM）, ultraviolet visible spectrophotometer（UV-Vis）, respectively. The performance of DSSC has been tested by solar simulator（Sun2000 Solar Simulator） and Autolab electrochemical workstation. The results show that the two dimensional TiO₂ nanosheet has good light scattering effect, and it can improve the photoelectric properties of DSSC.2. TiO₂ hollow nanospheres（THSs） were synthesized by a sacrifice template method. A bi-layer photoanode with TiO₂ hollow nanospheres as scattering layer and P25/multi-walled carbon nanotubes（MWCNTs） as under layer is designed for dye-sensitized solar cell（DSSC）.The crystal structure and microstructure of TiO₂ hollow spheres were characterized by XRD,FESEM, TEM, UV-Vis et al. The performance of DSSC has been tested by solar simulator（Sun 2000 Solar Simulator） and Autolab electrochemical workstation. The results show that TiO₂ hollow spheres can effectively scatter sunlight and improve the efficiency of solar light.Multi-walled carbon nanotubes can improve the conduction rate of electrons in the photoanode.