Light-trapping Structure Design For Luminescent Solar Concentrator Based On Perovskite Nanocrystals

Recent years,in the background of the increasing shortage and costs of global non-renewable resources,it is imminent to develop and utilize of clean energy such as solar energy.However,traditional solar cells have many shortcomings,for example,seriously affected by the lighting conditions,expensive costs,monotonous color and bulky volume,which affects the commercial process of solar cells.In response to these problems,research on luminescent solar concentrator has been put back on the agenda.The luminescent solar concentrator is composed of a waveguide structure coated with fluorescent material.The fluorescent material absorbs solar energy and emits light with a longer wavelength,which is transmitted to the edge through the waveguide structure and converted into electrical energy by the photovoltaic unit.Luminescent solar concentrator can effectively increase the photon density on photovoltaic cells,thereby reducing the covered area of solar cells.Currently,perovskite-based solar fluorescence concentrators have been successfully fabricated under laboratory condition.Due to its high optical absorption coefficient,high carrier mobility,high photoluminescence quantum yield,and low cost,perovskite is a promising new-generation base material of luminescent solar concentrator.However,there is a lack of systematic research on the structural optimization of perovskite-based luminescent solar concentrator.In this paper,based on FDTD Solutions software,anti-reflection structure and metal nanostructure are integrated into the perovskite-based luminescent solar concentrator,so that the absorption rate of the luminescent solar concentrator can be further improved.The main research work of this paper is as follows:（1）Four kinds of one-dimensional nanostructure arrays were exemplified,and their reflectivity was simulated.By comparing the reflectivity of different structures,combined with theoretical analysis,the influence of the size of the nanostructure on the reflectivity was summarized.The difference in anti-reflection ability of different cross-sectional shapes of the nanostructures is also explained.The results show that the nanostructures with a bottom width of 300nm and a height of more than 300nm can achieve ideal anti-reflection effects.The one-dimensional nanostructure array with a triangular cross-section has the best anti-reflection.（2）The optical properties of MAPb Br₃bulk material and nanocrystal material are simulated and analyzed.The results show that the nanocrystal material has both the high transmittance in the visible light band and the high absorption in the ultraviolet band,which combines properties of transparent dielectric and MAPb Br₃,so that it is believed to become an ideal base material for luminescent solar concentrator.On the surface of the nanocrystal film,one-dimensional nanostructure array is integrated into,which improves the absorption of the nanocrystals in the film layer and retaining the excellent anti-reflection ability of the nanostructure.The integrated of nanostructure also further improves the absorption of nanocrystals under low-angle incident light.（3）Between the MAPb Br₃nanocrystal film and the glass substrate,Ag nanowires are intergrated.The surface plasmon resonance of Ag nanowires are taken advantage of enhance the absorption of nanocrystal and broaden the absorption band.Furthermore,the composite structure is formed by the surface nanostructure and Ag nanowires at the bottom of the film,which extra improves the absorption of MAPb Br₃nanocrystal.At the wavelength of plasmon resonance peak of the nanowires,the high reflectivity caused by Ag nanowires can be reduced because of the anti-reflection properties of the surface nanostructure,and the absorption peak of the composite structure can be further improved.The above simulation work has certain reference value for the design of anti-reflection structures and the structure optimization of perovskite-based luminescent solar concentrators.