Preparation And Performance Study Of All-inorganic Copper-based CsCuX₃ (X=Cl/Br) Perovskite Single Crystal Material

In recent years,perovskite solar cells have attracted worldwide attention due to their high optical absorption coefficient,low preparation cost and easy preparation process.The photoelectric conversion efficiency of perovskite solar cells has increased from 3.8%to 23.7%.At present,the mainly perovskite materials used in solar cells,photo detectors and light-emitting devices are organic-inorganic hybrid lead-based perovskite materials.However,for the traditional organic-inorganic hybrid perovskite,the lead element in the materials is toxic to the environment and organisms,and once polluted,it is difficult to discharge from the body,which has been banned in many parts of the world.Therefore,the search for environmentally friendly non-lead elements to replace lead elements is one of the key points for the further development of perovskite.In this paper,an inorganic copper-based lead-free perovskite single crystal material was designed and synthesized by mechanical grinding and anti-solvent diffusion.We obtained the crystal structure and physical properties by X-ray diffraction,Photoluminescence,UV-Vis absorption and X-ray Photoelectron spectroscopy.The results were compared with those of all inorganic lead-based perovskite materials in order to provide theoretical support for the realization of lead-free and environmentally friendly perovskite.The content is mainly like below:1.Preparation of all inorganic perovskite single crystal materials.The inorganic lead-based CsPbBr₃ single crystal material was prepared by low temperature solution method.The optimum solvent ratio and growth temperature were investigated.For all-inorganic copper-based CsCuBr₃ single crystal materials,this paper explores the preparation method which combines the mechanical grinding method with the anti-solvent diffusion method,and successfully prepared all-inorganic copper-based CsCuBr₃ single crystal materials with good structure and optical properties.2.All inorganic lead-based CsPbBr₃ single crystal materials and all inorganic copper-based CsCuBr₃ single crystal materials were characterized and analyzed.The lattice constants and crystal systems of all inorganic lead-based CsPbBr₃ and copper-based CsCuBr₃ materials were calculated by XRD diffraction analysis.The proportion and structural characteristics of elements were given by EDS spectra.The fluorescence spectra and ultraviolet-visible absorption spectra of the two materials were characterized by fluorescence spectrophotometer and ultraviolet-visible spectrophotometer,and the basic optical properties of the two materials were obtained.3.Preparation and properties of halogen?Br/Cl?doped all inorganic copper-based perovskite materials.Three halogen-doped all-inorganic copper-based CsCuCl₁Br₂,CsCuCl_1.5Br_1.5 and CsCuCl₂Br₁ perovskite materials were prepared by mechanical grinding and anti-solvent diffusion methods.The effects of Cl ion doping on the structure and optical properties of all-inorganic copper-based CsCuBr₃ single crystal materials were studied.4.A series of ADP/DADP crystals were prepared by point seed crystal rapid growth method,and the thermal properties were studied.