High performance perovskite solar cells synthesized bydissolving FAPbI3 single crystal br

In recent years, CH(NH2)2PbI3 (FAPbI3) has received extensive attention due to the suitable band gap,becoming the most attractive photoelectric functional material in perovskite solar cells. However, the traditionalperovskite layer prepared by formamidine iodide (FAI) and lead iodide (PbI2) has inaccurate stoichiometricratio, high defect density, low stability, and low crystallinity, which makes it challenging to improve theperformance of perovskite solar cells further. In this paper, the perovskite film prepared by FAPbI3 singlecrystal has high crystallinity, high stability, accurate stoichiometric ratio and low defect density. The singlecrystal derived perovskite film has a large grain size and few grain boundaries, resulting in fewer defects in thegrain boundaries, which improves the short-circuit current density (JSC) and open-circuit voltage (VOC) ofperovskite solar cells, and greatly improves the photoelectric conversion efficiency. This work provides anefficient strategy for fabricating perovskite solar cells with high stability, high crystallinity, and low defectdensity