Simulation Of Dye-sensitized Solar Cells Using COMSOL Multiphysics

Energy is one of the main driving forces for the rapidly developing world.The development and utilization of solar energy is the key focus to solve the problems of energy shortage and environmental pollution.Dye-Sensitized Solar Cells（DSSC）are thought to be a candidates to realize the large-scale use of solar energy due to their advantages of low cost,safety,stability,and high conversion efficiency.And the structure and composition of the photoanode of DSSCs are the main factors that affect the conversion efficiency,as a result,the various properties of nanomaterials and their structures in the photoanode are research focus all over the world in recent years.Furthermore,photoanodes with different nanostructures,such as nanowires,nanorods,and nanotubes can improve the specific surface area of the materials to a certain extent,so as to achieve the purpose of improving the photoelectric conversion efficiency.In this paper a complete two step photoelectric coupling model was built by COMSOL Multiphsics software to reveal the photoresponse and current transport processes of DSSC,which is under the simulation environment of external electromagnetic field,temperature field andelectrostatic field.Specifically,an optical model is studied to determine how much the solar energy each cell takes in,and an electrical model is investigated to determine how much the overall efficiency.Besides,according to the propagation mechanism of solar light in DSSC and the electron diffusion mechanism in the photoanode,the photoanode structure of the conventional TiO₂ thin film DSSC is optimized.Specifically,a layer of electrical conductivity is inserted into the photoanode of the cell,which allows more sunlight to scatter inside DSSC for improving the light capturing capability of DSSC,and shortens the diffusion distance of the photoelectron on photoanode semiconductor for reducing the recombination rate of conduction band electrons,so the overall photoelectric conversion efficiency of DSSC is improved.Compared with traditional TiO₂ thin film DSSC,three optimized photoanodes,which are named planar and sin curved surface singly separated conductive layer TiO₂ film,double plane separated conductive layer TiO2 thin film,have improved the photoelectric conversion efficiency of DSSC by 11.7%,7.2%and 28.84%,respectively.The study shows that it is an effective method to improve photoelectric conversion efficiency by reasonably optimizing the photoanode nanostructures of DSSC.