Modification And Photoelectrochemical Research Based On Nanocrystalline TiO₂ Photoanode

Energy source is limited, and it becomes serious problems that affect human survival and development. Therefore the development of new energy and new energy materials is a major issue to be solved. Dye-sensitized solar cells become an effective way of utilization solar energy, as its low cost, simple production and potential photoelectric conversion efficiency.TiO₂ photoanode plays an important role on determining the performance of a dye-sensitized solar cell (DSSC). Porous photoanodes materials and photoanode microstructure effect on the energy conversion efficiency of DSSC. In this paper, the photoanodes material was prepared by N-doped TiO₂,and its photoelectric properties and resistance properties were studied to compare with P25 films. A titanium organic sol was synthesized for the modification of conventional porous TiO₂ photoanodes for DSSC to study its photoelectric properties; Different size of nano particles was mixed to prepare photoanodes, and photoelectric properties were studied.By the method of high temperature oxidation TiN in air, N-doped TiO₂ mixed with rutile and anatase was prepared. N-doped TiO₂ was investigated by XRD,SEM,XPS,UV-vis,photoelectric properties,EIS。The results showed that the N-doped TiO₂ which prepared by oxidation TiN at 550℃for 30 min have better photoelectric properties than P25. EIS showed that the interface resistance of N-doped TiO₂ film/electrolyte was smaller than that of P25/electrolyte. Electron transfer efficiency was improved and hence a higher energy conversion efficiency.A titanium organic sol was synthesized for the modification of conventional porous TiO₂ photoanodes for DSSC to improved electron transfer pathways, so as to improve the photoelectric conversion efficiency. This method was better than the traditional TiCl4 modification method. A high efficiency dye-sensitized solar cell was fabricated by composite 20 nm P25 and 100 nm TiO₂, control the quality of the two nanoparticles to adjust the pore size of nanoporous films, to improve photoelectric conversion efficiency. The results found that a high efficiency dye-sensitized solar cell was prepared by the composite anode which was fabricated by the 20 nm P25:100 nm TiO₂ ratio of 75%:25%, the open-circuit voltage of 699 mV, the short-circuit current density of 6.50 mA·cm-2, a FF of 0.69 and an overall power conversion efficiencies of 3.13% was achieved under 100 mW·cm^-2 illumination with a solar simulator.