Application Of Down-conversion Phosphor In Dye-sensitized Solar Cells

With the rapid development of economy, the world’s demand for energy isincreasing; the energy problem has been an issue all over the world. Due to variousdefects, the traditional energy can not meet people’s need. What’s worse, it is notsustainable, so the research on new energy is imminent. Among much new energy,solar energy reserves is huge, and it’s clean and sustainable. Due to advantages ofsolar energy, it has drew many scientists’ attention. Solar cells is a good option.Currently, the third generation of solar cells—dye-sensitized solar cell（DSSC） hasaroused much interest. Now the conversion efficiency of DSSC has exceeded13%,meanwhile, further improving efficiency and reducing costs is the goal of thescientists.So far, scientists have proposed many solutions, such as new semiconductor film,a new type of dye and electrolytes. But now the most used is still N719, it absorbssunlight in the300-600nm wavelength range. Ultraviolet and infrared light whosetotal energy exceeds half the energy of the sun can not be utilized. What’s more, UVis harmful to the dye and electrolytes, so if the ultraviolet could be converted tovisible region which can be absorbed by the dye in DSSC, which not only improvesthe efficiency of DSSC, but also extends the service life.In this paper, converting ultraviolet light to the visible region about550nmwavelength where N719has greatest absorption efficiency is our target. We haveprepared various phosphors based on Y2O3, YF3, and Tb3+, Dy3+ions act as activator.At last,the phosphor was applied to DSSC.(1) Y2O3:Tb3+nano-phosphors were prepared using hydrothermal-hightemperature solid phase method. Both the open-circuit voltage and short-circuitcurrent densities of the doped DSSC have increased; the cell ‘efficiency can reach7.942while the doping amount is4wt%.(2) YF3:Tb3+nano-phosphors was prepared with hydrothermal method, and thenintroduced to DSSC. Both the open-circuit voltage and short-circuit current densitiesof the doped DSSC have increased, the cell’ efficiency can reach8.405while thedoping amount is4wt%.(3) Y2O3:Dy3+nanorods have been successfully synthesized by a hydrothermalmethod and introduced into the TiO2film in Dye-sensitized solar cell. As a p-typedopant, Y2O3:Dy3+enhances its Fermi level. What’s more, it also improves thelight-to-electric energy conversion efficiency by converting ultraviolet light to visiblelight. The conversion efficiency can reach7.521%when the doping amount is3wt.%.