Perovskite Solar Cells Based On New Type Hole-transporting Materials

Perovskite solar cell?PSCs?is a rapidly developing photovoltaic device in recent years,because of its simple preparation process?mainly liquid phase deposition and gas phase deposition?,power conversion efficiency?PCE?improved rapidly?3.8%in 2009and over 22%in 2017?and possibility for manufacture of flexible devices,which have been expected for a broad application.Perovskite thin films strongly influence the performance of the solar cells as light absorption layers,in this paper,from the material of perovskite materials,the crystal structure,basic characteristics and ionic migration of organic halide hybrid perovskite materials are introduced.Then,the process of the reverse solvent Flushing one step?anti-solvent one-step method?used in the preparation of MAPb I₃ film is introduced,and the scanning electron microscope?SEM?and the microstructure,composition and crystal surface information of the MAPBI3 films prepared by X-ray diffraction?XRD?were analyzed,and it was proved that the perovskite films prepared by this method had better film forming quality.In addition,in the synthesis of perovskite thin films,we have studied the effect of ethanol solvent annealing on perovskite thin films,demonstrated the SEM and XRD results of the films after solvent annealing,and compared with the perovskite films without solvent annealing,we found that the film with ethanol solvent annealing has better film forming quality,but its crystal surface structure has changed.In addition,this paper introduces the working principle,device structure and working parameters of perovskite solar cells,and introduces a new type of hole-transporting layer.The NiO_x?nickel oxides?films doped with lithium salt and magnesium salts were prepared by spray pyrolysis,and a planar perovskite solar cell with FTO/NiO_x/CH₃NH₃PBI₃/PCBM/Ag device structure was successfully prepared.Its optimal energy conversion efficiency reached 12.20%.It is observed that the prepared perovskite solar cells based on Ni O_x films have been placed under ambient conditions for a period of time,the performance of the device has obviously decreased,the silver electrode corrosion phenomenon,which is different from our predicted device stability.Based on the degradation mechanism of perovskite films and the corrosion principle of metal top electrodes,it can be inferred that the degradation of properties and the causes of electrode corrosion.By setting the contrast experiment to control environmental humidity,the Fourier transform infrared spectroscopy?FTIR?and X-ray photoelectron spectroscopy?XPS?testing method were used to analyze the observed phenomena.The results verify our hypothesis that the humidity is the important reason for the degradation of perovskite films and the corrosion of silver electrodes under natural conditions.