Research On Perovskite Solar Cells Modified By Solid And Gaseous Organic Amines

Since the invention of perovskite solar cells（PSCs）in 2009,their superior performance has attracted the attention of more and more researchers.The efficiency of PSCs increased from 3.8%to 25.5%.CH₃NH₃Pb I₃（MAPb I₃）is the most frequently used perovskite active layer material in device preparation due to its high extinction coefficient,high carrier migration rate and long transmission distance.However,the unmodified MAPb I₃ film has a low coverage rate,and its surface defects and pinhole structure reduce the film’s light absorption capacity and stability.Therefore,high quality perovskite film is the prerequisite for the preparation of efficient and stable battery devicesBased on the above background,large-scale organic amine salts（benzylamine hydrochloride and phenethylammonium iodide）were used to assist the preparation of high-quality MAPb I₃ films and perovskite cell devices.In addition,the reaction mechanism between amine gas and MAPb I₃ perovskite was studied in this paper,and2D perovskite film was prepared with the assistance of diethylamine gas and applied to the battery device.The specific research contents are as follows:In the experiment,benzylamine hydrochloride was used to doped the perovskite precursor,and the prepared MAPb I₃ film was compact,and had good light absorption capacity within the range of 350-800 nm.The perovskite crystal was highly oriented at（110）and（220）crystal surfaces.The perovskite device based on 0.2M benzylamine hydrochloride doping has an efficiency of 10.67%,an open circuit voltage of 0.91V,a short circuit current of 17.16m A/cm²,and a filling factor of 68.33%.The wide-band gap PEA₂Pb I₄ two-dimensional perovskite formation was induced by different concentrations of PEAI solution.The device based on PEA₂PBI₄-MAPBI₃ film has an efficiency of 14.47%,low carrier recombination rate,and excellent stability under high humidity.In this paper,diethylamine（DEAV）was used to modify the perovskite film,and a（DEA）₂PBI₄-MAPBI₃ perovskite absorbent layer was obtained.Based on this structure,the device’s photoelectric conversion efficiency reached 16.01%.In addition,the doping of liquid perovskite intermediate（LPI）to MAPb I₃ can enhance the grain size of perovskite,improve the interface contact,and thus reduce the contact resistance.The optimal efficiency of the device based on LPI doped film reaches17.10%,and the open-circuit voltage is increased from 0.8V to 1.05V.